Free Jewelry Dictionary. Have you ever come across jewelry-making terms like “sagenite,” “pillions,” or “gangue” without knowing their meanings? We’ve made it easy for you! This dictionary of standard—and some not-so-common—terms for jewelry artists will guide you through the intriguing world of jewelry making. You’ll never have to wonder what “adularescence” means again!
Let’s Explore Our Free Jewelry Dictionary
A
Abrasives The grits, usually silicon carbide or dia mond, used to shape gemstones.
Acetylene Torch Portable silversmithing torch which burns acetylene and air.
Adamantine The diamond-like luster of certain gems.
Adularescence A milky reflection of light on a gem such as the blue or silvery appearance of moon stone.
Airbrasive Unit A small-scale sandblaster used with a vari ety of powdered abrasives for the delicate cleaning of fossils.
Alcohol Lamp A small lamp often used for dopping cabo chons or faceted stones.
Alloy Two or more metals in combination. (For example, sterling is silver plus copper.)
Almag An oil often used as a coolant for slab or trim saws.
Alumina Highly refined aluminum oxide used as a polishing agent.
Aluminum Pencil This pencil leaves guidelines on stones which will not wash off.
Amber Fossilized tree sap, occasionally containing preserved insects as inclusions.
Ammonite A group of mollusks (molluscs) extinct since the Cretaceous Period whose mod ern relatives include the chambered nauti lus, squid, and octopus.
Amorphous Meaning formless; describes gem materi als without orderly atomic structure.
Angle Pointer Points to the desired angle on a faceting head.
Angle Quadrant Shows the degrees from 0 to 90 for facet ing angles.
Angle Stop Prevents accidentally overcutting the desired angle on a faceting machine.
Asterism A quality present in some gem materi als which makes it possible to cut “star” cabochons. Inclusions make the stars possible.
Anode The positive terminal of an electrolytic cell used with a plating solution.
Anti-oxidant Liquid applied to places solder should not flow.
Antiquing Applying a finish to jewelry to make it look old. For example, using liver-of-sulfur to blacken silver.
Anvil Metal stake used for forming or raising metal.
Apex The bottom point of a faceted stone.
Appliqué Laying one layer of metal upon another to produce dimension and design.
Arbor A rod, bar, or shaft which holds the wheels for cutting, grinding, sanding, and polishing.
Art Deco Jewelry of the early 20th century featuring abstract and geometric lines.
Art Nouveau Jewelry of the turn of the 20th century with flowing lines and realistic motifs.
Assembled Carving A carving made of several parts, often of different materials and colors assembled into one unit.
B
Baculite A common uncoiled ammonite of the late Crustaceous Period.
Baguette A facet cut for small gems, step cut, and rectangular.
Bail Holder for the top of a pendant. Leather as a Jeweler’s Tool Lapidary Journal Jewelry Artist, April 2014
Bangle A rigid, entirely round, loose-fitting brace let.
Bar Pin Narrow decorative pins of a more or less rectangular shape.
Barion A mixed facet cut combining emerald cut crowns with brilliant cut bases.
Baroque Pearl A pearl of irregular shape.
Bas Relief A low relief carving — raised slightly above the background material.
Basse Taille A transparent enamel technique with repoussé.
Bead Board A wood or plastic grooved board for arranging bead necklaces before stringing.
Bead Mill A machine to finish spherical beads.
Bead Thread Silk or nylon thread of various sizes for beading.
Bead Wire Fine nylon-coated wire for beads.
Bearings Supports for rotary shafts of revolving lapi dary machines.
Beeswax Used for cementing and dopping.
Belcher Mounting Pronged modification of the gypsy mount ing for rings.
Bell Cap A metal bell-shaped cap with loop top for attaching stones.
Bench Pin A notched hardwood pin to be attached to the workbench to hold jewelry during specific stages.
Bench Vise A small vise with can attach the pin or vari ous other tools to the workbench.
Bevel A small rim around the bottom edge of a cabochon with an angle of about 45 degrees.
Bezel A shape made of flat wire to hold the stone in place in a piece of jewelry.
Bezel Pusher A tool to flatten and smooth the edge of the bezel firmly around the stone.
Bezel Wire A metal wire with a collar and sometimes fancy designs for making bezels.
Biaxial Stones with two optic axes and directions.
Binding Wire A soft iron wire for holding together parts to be soldered.
Birefringence Doubly refractive materials.
Blank A piece of gem material which was been sawed and ground to the approximate size and outline of the planned cabochon.
Blazer Blades Modern long-lasting diamond saw blades.
Bobbing Compound A fine abrasive which leaves metal scratch free with a dull finish.
Bola Slide The slide which moves up a bola tie cord.
Bola Tie A neckpiece consisting of a length of cord with tips and held together by a movable slide of metal and often set with a stone.
Borax Mineral powder used as a flux to control oxidation during melting of metal. Also, when combined with boric acid, used for flux during soldering.
Bort Industrial diamond for lapidary purposes.
Botryoidal A smoothly curved group of rounded mounds on some gem rough which resem bles a pile of marbles or grapes.
Boule The pear-shaped gem material resulting from early synthetic production.
Box Clasp Fiesta Bonefish Step by Step Wire Jewelry, August/September 2014 A standard box-shaped jewelry clasp with a tongue which slides into the end opening.
Brass A copper-zinc alloy used for jewelry and decorative objects.
Breccia Cutting material made of angular bits which have been naturally cemented together by some mineral, often chalcedony.
Brick A brick is often used for initial cuts and for deglazing diamond saw blades.
Brilliancy The total light reflection of a gemstone.
Brilliant A basic facet cut of 58 facets, primarily for round stones.
Briolette A drop-shaped facet cut with the crown similar to the rose cut.
Britannia Metal Modern pewter alloy of tin, antimony, and copper.
Bronze An alloy of copper and tin.
Bruce Bar A patented polish compound in stick form.
Buff The wheels or pads used for polishing gem materials. Usually leather, felt, muslin, Pellon, etc.
Bur Carbon steel tool which can be one of 30 or more shapes to be used in a flexible shaft tool.
Burnisher Oval-shaped blade tapering to a fine point for setting stones and smoothing metal.
Bushing A replaceable lining for a bearing or the removable cylindrical lining of the grinding wheel holes
C
Cab Mate Complete cabochon machine with light.
Cable Chain Simple chain with interlocking identical links in a pattern of vertical links connected by horizontal links. Cabochon A polished gemstone with a flat bottom and domed top, usually oval or round (not faceted). However, cabochons may also be shapes such as hearts, crosses, freeform, and other shapes.
Cabochon Unit A combination machine used for making cabochons from the sawing through pol ishing stages.
Cameo An engraved cabochon, usually cut from a color-layered material.
Champlevé An enamel technique in which depressed areas in the metal are filled with enamel.
Carat A unit of weight for gemstones. There are 5 carats to a gram. Carborundum Silicon carbide. Synthetic hard material used for grinding wheels, cutting and sand ing grits, and lapidary tools.
Carriage That part of the saw which feeds the mate rial into the blade.
Casting Flask Steel flask to hold the investment for cast ing.
Casting Machine Any of several kinds of machines made for casting metal.
Cat’s-Eye The phenomenal property of some gems with fiber or tube inclusions to produce luminous “eyes” if properly oriented.
Caulking Compound Used as a grout for some mosaics.
Centrifugal Caster A casting machine with a heavy spring which swings the arm to force the molten metal into the flask.
Ceramic Soldering Block A lightweight, fire-proof, smooth block for soldering.
Chamois Buff A wheel buff or hand buff with chamois surface for polishing jewelry.
Channel Stone inlay in a metal framework of flat wire cells.
Charge Impregnating a grinding or polishing wheel or disc with the desired compound.
Chasing Texturizing metal with chisel-like tools.
Chasing Hammer A hammer with a large flat head used for striking the chasing tool.
Chatelaine A metal pin with swivel chains for hanging objects such as a watch, keys, scissors, etc.
Chatoyance The phenomenal quality of some gems to reflect movable light bands.
Cheater A faceting machine device for moving a mounted gemstone sideways.
Chinese White A white substance which is brushed on metal so a pattern or design can be drawn on it.
Chrome Oxide A dark green polish powder often used for jade.
Chuck An attachment for holding the mounted preform or other piece of work. A clamp for holding the dop sitck for a faceting handpiece.
Clamps Usually refers to C-clamps, which have a C shape and a threaded bolt which can be tightened to hold two parts together.
Cleavage The property of a crystalline material to break in a specific way, leaving a some what smooth break.
Cleavage Angle The angle created between cleavage faces when a mineral is split.
Clipped Solder Metal solder which can be purchased ready for use in bottles of 1mm squares.
Cloisonné Cells of rectangular wire are placed in a pattern on a metal surface, filled with enamel, and fired.
Cluster Ring A ring made to set a group of small stones.
Coin Jewelry Coins mounted to wear as jewelry.
Cold Dop A method of dopping sensitive stones with cold cement.
Collet Hammer Hammer with a double head, one part domed, the other a modified shape.
Collet Setting Setting with the stone in a metal collar.
Conchoidal A shell-like fracture of concentric smooth curves found in some minerals such as obsidian.
Concretion A concentration of sediments harder than surrounding rock and usually formed around a nucleus. Conglomerate A cutting material in which rounded grains and pebbles are naturally cemented together by chalcedony or another agent. Contaminant Harder or larger particles on laps or buffs which cause scratches on stones.
Copper Tongs Used for removing metal from pickle.
Core Drill A tube drill which cuts cylinders of stone.
Cork Lap A lap used for cabochons and small flats.
Costume Jewelry Fashion jewelry. Jewelry which keeps pace with current styles and fads.
Crown That part of a faceted stone which is about the girdle.
Crucibles Containers for melting metals.
Cryptocrystalline Materials with microscopic crystalline structure. Crystal A solid with regular atomic internal arrangement bound by definitely patterned external planes.
Crystalite Discs Fast cutting diamond discs.
Crystalline Materials with precise atomic internal structure but without the external shapes composed of definite planes.
Cuff Bracelet Wide rigid bracelet with narrow opening.
Culet The bottom facet on the pavilion of a bril liant cut stone.
Cultured Pearls Induced pearls of various shapes and col ors grown in pearl farms or fisheries and widely used for jewelry.
Curb Chain A chain with flattened links each fastened to the next in the same manner.
Cushion A facet cut shaped like a square with rounded corners.
Cutter A lapidary.
Cuttlebone Casting Carving patterns in cuttlebone for direct casting.
Cylinder Cylinder-shaped cut stones, often with engraved designs
D
Dapping Block Blocks with dies and punches to fit, for shaping metal.
Dapping Punch When tapped with a hammer in the die, forms half a dome.
Dendritic Moss- and branch-like shapes and mark ings; developed during crystallization of ore and manganese compounds, often caused by manganese or iron minerals.
Dental Tools These small, well-made tools are used by carvers.
Diamond Cut Brilliant engraving cuts on metal for greater luster.
Diamond Drill A gem drill using diamond points.
Diamond Dust Also called diamond powder or diamond grits, used in cutting and polishing gem stones.
Dopping Wax Any of several kinds of wax used to attach stones to a dop stick.
Double Cabochon A cabochon which is rounded or domed on the bottom as well as the top. Two-sided cabochon.
Doublet A gemstone made of two layers of material.
Dowel Round wood rods used for dop sticks.
Draw Plates Strong metal plates with many holes for changing wire’s size or shape.
Drawing Wire can be reduced in size or changed in shape by pulling through the draw plate.
Dremel Tool Motorized variable speed handpiece for working on stone.
Drill Bits The points used in a machine for drilling which do the actual cutting.
Diamond Paste Diamond particles in a paste compound.
Diamond Saw A gem-cutting saw with the blade edges with diamonds.
Diamond Wheel Grinding wheel with diamond-impregnated surface.
Diamond Wheel Dresser Tool used to true the silicon carbide grind ing wheels.
Dichroism Literally two colors. A gemstone with this property shows two colors when viewed from different directions.
Dispersion The separation of white light into the col ors of the spectrum.
Dop Also dop stick. A rod of metal or wood to held the gemstone during the required stages for finishing it.
Dopping Block A faceting machine device for correctly aligning two dop sticks for the transfer process.
Drill Press A machine which holds the drill and the work to be drilled.
Drop Casting Dropping molten metal into ice water for freeform shapes.
Drum Sander A sanding wheel for abrasive belts, either strip or endless. Some drum sanders are expandable.
Drusy Cavities Hollow spaces within a rock, such as vol canics, that are filled with a collection of secondary minerals.
Dust Collector A system of filtering dust from the air of a lapidary shop. Combinations of blowers, filters, and suction.
Dwt Abbreviation for the troy weight unit “penny-weight.
E
Earring Jacket A thin stone or metal pattern drilled for an earring stud.
Easy-Flow Solder Coiled wire soft solder with a low melting point.
Electro-Etching A method of etching metal surfaces with electroplating equipment.
Electroforming Building up metal on a disposable form using electroplating equipment.
Electroplating Depositing a coat of metal over another metal by electrolysis.
Emerald Cut Same as step cut. A basic facet design, usually rectangular or square, with rows of parallel facets.
Emery A mixture of finely granulated corundum, magnetite, hematite, ilmenite, and quartz.
Emery Cones Used on tapered spindles to sand the inside of rings. Enamel Glass frit which is applied to metal and fired to color the metal and produce a design.
Engraving Incising designs in metal or stone with sharpened steel gravers.
Enhancer Pendant with clamp which will fit over pearls or beads.
Enhydro A stone containing a section which is par tially filled with water.
Etching A process of producing a design upon stone or metal using corrosive acid.
Extender A fluid used to dilute and spread diamond paste or powder
F
Fabulustre A stick type of polish compound.
Facet A flat polished surface on a gemstone, usually a transparent stone, and usually in combination with other flat planes in a spe cific design. Also a small surface displayed by a crystal that is naturally occurring from growth, as in crystal faces.
Faceting Head That part of a faceting machine which is moved up and down on a rod and can be adjusted to the proper angle to cut the facet.
Faceting Saw A small thin diamond saw for preliminary cuts of facet rough.
Fantasy Cuts Novel new combination cuts which have concave “facets” and elements of cabo chons, flat facets, and carving.
Feathering Disc Adhesive Cement for bonding abrasive discs to pads.
Feldspar A group of rock-forming silicate miner als with the subgroups orthoclase and plagioclase.
File-a-Wax Wax to be shaped by files for lost wax models.
Files Principal jewelry files are flat, mill, half round, and round.
Filigree Spiral wire units forming lacy designs in flat metal framework.
FinaLap A metallized resin lap for faceting.
Findings Parts for making jewelry complete, such as pin backs, bola tips, bell caps, bails, jump rings, etc.
Fine Grind The last grinding process before sanding.
Fine Silver Pure silver, not alloyed.
Fire The flashes of different colors in gems resulting from the breakup of white light.
Fire Scale A deposit of dark cupric oxide on the surface of alloyed metals such as sterling because of overheating or not enough flux.
Fishhook Clasp Hook shape which fits in decorative metal oval.
Flanges Discs to hold lapidary wheels and saws in place. Flannel Buff Cotton buffing wheel used with rouge.
Flask Stainless steel cylinder with matching sprue base for casting.
Flask Tongs Long-handled tongs for handling hot flasks.
Flats Either slabs or flat areas on stones which should be curved.
Flaws Fractures or inclusions which mar the stones and should be avoided in the cutting process.
Flexible Shaft Handpiece A motorized hand-held piece of lapidary equipment with variable speed, which can hold a variety of cutting, grinding, and polish ing tools, especially for carving.
Foredom A popular brand of flexible shaft handpiece and tools.
Forging Forming metal by raising it with a hammer over a stake.
Foxtail Fine nickel chain for heavy beads.
Freeform A stone which is not cut in a regular or standard geometric shape
Fused Metals Fusing scrap metal onto a preformed metal back
G
Gangue The relatively worthless rock or vein material in which valuable metals or min erals occur.
Gauge A device for measuring the exact dimen sions of a gemstone.
Gear Trigger The trigger which holds the notched gear at the top of a faceting head.
Gear Wheel A 60 notch wheel used for many kinds of facet cuts.
Gem A cut and faceted stone, often for jewelry use.
Gem Maker Complete combination unit.
Gem Master Facet machine with electronic micro stop.
Grain A tiny crystalline particle or a unit of weight which is one quarter of a metric carat.
Gram A metric weight — 28.34 grams to an avoirdupois ounce. Gram Weight Set A set of metal weights from 500 mil ligrams to 100 grams, for weighing jewelry metals.
Granulation Decorative and texturing metal process of solderless bonding of tiny beads of gold to the surface by heating.
Gravers Steel tools for engraving designs or letters, available with ends of many shapes such as chisel, bevel, flat, lozenge, round, and square.
Gem Material Rough mineral or rock which can be cut into gemstones.
Gemstone A mineral, synthetic, or organic stony material which has sufficient beauty and hardness (or toughness) to be used for decorations or adornment.
German Silver An alloy of nickel, copper, and zinc.
Gilding Covering a metal surface with “gild,” a mixture of gold and mercury. Also covering with gold leaf.
Girdle The outer edge of a faceted stone or the dividing line between the crown and pavil ion.
Goggles Safety goggles should be worn for such steps as melting metal, centrifugal cast ing, etc.
Gold Filled A core metal such as nickel laminated between gold sheets. Must be stamped, for example 1/20 G.F. or 1/20 10K G.F.
Gold Plated A thin (usually) gold covering on jewelry or other objects deposited by electroplating.
Gold Solder For soldering gold jewelry — available in low karat up to 18K, in clipped, strip, and wire form in yellow or shite.
Gold Test Kit Acid bottles with test needles and touch stone for determining karat content. Steel tools for engraving designs or letters, available with ends of many shapes such as chisel, bevel, flat, lozenge, round, and square.
Green Wax A standard dop wax for cabochons.
Grinding Wheel Silicon carbide or diamond wheels to grind gemstones into desired shapes.
Grit Loose grits, or grits in binders, are abra sives of various sizes, usually silicon car bide or diamond, used for lapidary work.
Grout A cement which is used to fill spaces between stones of mosaics.
Gum Tragacanth Used as an adhesive in the enameling process.
Gypsy Setting A wide-domed ring with a flush set stone which continues the curve of the dome.
Gyrock Cabber A machine with six cab heads designed to make perfect cabochons consistently.
H
Half Dome Formed by dapping a circle of metal into adie block.
Hallmarks Registered craftsman’s marks stamped on jewelry items.
Hard Solder Gold or silver solder with a melting point of 1365°F and a flow temperature of 1450°F.
Hard Stone Hard stones for jewelry are those 5-10 on the Mohs scale.
Hardness How hard one stone is in comparison to others is measured by lapidaries chiefly with the Mohs scale, which rates talc as 1 and diamond as 10.
Hastings Triplet A three-part 10X magnifying loupe for viewing stones.
Healed Fracture A previously fractured piece of gem mate rial naturally filled in by chalcedony or another mineral.
Heat Color The various colors of yellows and reds which indicate the temperature of a molten metal.
Heat Sensitivity The characteristic of some gem materi als to chip or break easily when exposed to heat.
Heat-Treated Subjected to a process of heating (espe cially precious stones) to change the color.
Hemostat A versatile locking pliers which can be used while soldering.
High Dome Cabochon A cabochon with an unusually steep curved top, very often a star stone.
Highland Park Tumbler Steel barreled tumbler with nylon bearings and plastic-covered roller shafts.
Hopper Same as barrel for tumbler, but often used for vibrating tumbler nomenclature.
Hot Dop An electric unit for heating dop wax and the stone to be dopped
I
Inclusions Irregularities, usually of foreign material, enclosed within gem materials, such as liquid- or gas-filled tubes, feathers, flakes, needles, crystals, etc.
Index Wheel Disc which regulates the stone setting on a facet head.
Inlay Positioning a gem material pattern in recessed soft material such as slate. Also inserting a stone design in metal.
Intaglio A gem engraving similar to a cameo but concave instead of convex.
Intarsia A gemstone picture made up of many precisely shaped pieces of material fitted together on a base of stone or wood. Also Florentine mosaic or pietra dura.
Investment A plaster-like material which is mixed with water and poured around the model to be cast in the casting flask. Also called cristobalite.
Iridescence A changeable multi-colored effect in gem materials such as spectolite, caused by light interference.
J
Jacobs Chuck Fits on a threaded shaft and holds a variety of tools for carving.
Jamb Peg An early faceting device with holes to sup port dop sticks at the proper angles.
Jewel An ornament, usually of precious metal, set with a cut and polished gem or pearl. Also a cut and polished gem.
Jeweler’s Eye A portable device to aid in identification of gemstones.
Jeweler’s Saw A rigid, metal, adjustable frame with wood en handle and straight replaceable steel blades of various sizes.
Jewelry Cleaner A liquid cleaner for jewelry for use with or without an ultrasonic machine, a steam cleaner, or a jet cleaner.
Jewelry Pins Gold- or silver-colored “u” shaped pins ending with an upright curve.
Jobber A wholesaler who distributes imported or American-produced materials and supplies to retailers.
Jump Rings Round or oval metal rings which are used to link two parts together. Made with a slit opening which is usually soldered shut after being put to its intended use
K
Karat A measure of the purity of gold. 24K is pure, 12K is half gold, and less than 10K is usually not stamped as gold.
Karat Stamp Metal stamp for incising metal content.
Kerf The width of the cut made by the saw blade.
Keyhole Router A diamond tool designed to remove mate rial for the inlay process. Also used as a drill.
Kiln Burnout oven for casting or enameling.
Kimberlite Pipe Volcanic, pipe-shaped structure filled with kimberlite rock that might contain dia monds.
Kool Jool A preparation for coating jewelry parts which must be kept cool during soldering.
L
Labradorescence A phenomenon caused by the lammular structure of some gem materials producing bright reflected flashes similar to irides cence, but not multi-colored.
Lap A horizontal revolving disc for grinding and polishing gems.
Lap Stik A two-sided sticky tape to hold slabs to laps.
Lapidary A person who works with stone, primarily gemstones. Also used as an adjective to describe the shop, the kind of material, and the equipment used in cutting stones.
Lathe Rotating machine which can be used to make vases, bowls, etc
Lavaliere Small jeweled pendant, often with fine chains.
Leather Buff A popular surface for polishing gems.
Lemon Peel Also called orange peel. The appearance of materials pitted by undercutting, due to irregular grain structure.
Limoges An enamel style similar to a painting in appearance.
Linde A An excellent aluminum oxide polish for many materials.
Little Torch A miniature oxygen and gas torch which welds, brazes, or solders areas hard to reach with conventional torches.
Liver-of-Sulfur Potassium sulphide, often used to antique metals.
Lobster Claw A safe jewelry clasp.
Locket A hinged pendant, often round or heart shaped.
Locking Tweezer Used to get a firm grip on small objects.
Lost Wax A casting process where the burnout melts the wax model and molten metal is forced into the mold.
Loupe A magnifying device for inspecting gem stones.
Low Dome Cabochon A cabochon with a very slightly curved top.
Lubricant Also coolant. A liquid for keeping the machinery and/or gem material cool.
Lucite Lap A plastic lap for faceting.
Luster The optical effect resulting from light reflected from the surface of gem material. Examples: silky, pearly, vitreous
M
Main A principal facet.
Malleable The property of metals to be formed with out breaking.
Mandrel A tapered spindle for sizing and shaping items such as rings.
Marquise A double pointed cut for a faceted stone.
Married Metals The Mexican term for lamination of sev eral metals in one piece of work.
Massive Material not occurring in external crystal form.
Matrix The rock in which the gemstone occurs, often polished with it such as matrix opal or emerald-matrix.
Matrix Mount Preparing a fossil for display, usually with out removing it from the original matrix in which it was found.
Matte Finish A velvety, non-shiny finish.
Media Abrasives embedded in plastic used in vibratory tumblers.
Mesh Size A measurement of particle size in grinding or polishing powders.
Metric Weights A system of weights used particularly for facet material.
Mirror Finish A bright, glass-like finish.
Mizzy Wheel Small heatless grinding wheels for use in flexible shaft tools for carving.
Mohs Scale A commonly used scale of relative hard ness of minerals. 1. Talc. 2. Gypsum. 3. Calcite. 4. Fluorite. 5. Apatite. 6. Feldspar. 7. Quartz. 8. Topaz. 9. Corundum. 10. Diamond.
Mokumé A Japanese method of texturing metal to resemble wood grain
Monel Metal A nickel copper alloy.
Mordant Etching solution of acide and water.
Mosaic Pebbles or pieces of cut stone cemented to a base to form a pattern or picture.
Motif The theme of a design.
Mount To rebuild a fossil skeleton for display.
Mourning Jewelry Victorian fad often done in black or featur ing portraits.
Mud A mixture of water and grit used as an abrasive for sawing. Mud Saw A revolving steel wheel which cuts with silicon carbide abrasives mixed with water.
Muriatic Acid A dilute acid which is sometimes added to a polish slurry (only a few drops) for such soft cutting materials as calcite.
Muslin Buff Multiple circles of unbleached muslin are sewn together for a high speed pol ishing buff.
MX Wheel Cut-off wheel of aluminum oxide-impreg nated muslin for cutting metal
N
Nacreous Having the luster of mother-of-pearl.
Navaratna Traditional nine-gem jewels of India.
Needles Elongated crystals, such as rutile, often found as inclusions in gem material.
Netsuke Small carved toggle used to attach a small container to a kimono sash.
NGraveR Electric engraving machine.
Nibbling Preliminary step in shaping a cabochon preform by breaking off small bits with nip pers or pliers.
Nickel Hard white metal used for plating or alloying.
Nickel Silver An alloy of copper, nickel, and zinc.
Niello Blackened silver alloyed with sulfur and copper and fired onto the workpiece.
Nodule Rounded or almond-shaped lump of min eral or aggregate, typically in siliceous volcanic rocks.
Notch Rim Blade A diamond saw blade made of steel with notches on the edge holding the diamond charges.
Novaculite A uniform, fine-grained material from Arkansas used as a sharpening stone for tools.
Nugget A small, natural, irregular lump of material, such as turquoise nugget.
O
Ochre Yellow-to-brown-colored mixture of differ ent iron compounds such as hematite and limonite.
Old Mine A facet cut which is the predecessor of today’s brilliant cut.
Oolite Sedimentary rock made up of very small spheroidal granules often of calcium car bonate cemented together.
Opalescence A phenomenal quality in some gems which milky or pearly.
Opaque Gem material which does not transmit light, such as jasper.
Optic Axis A direction in a doubly refractive crystal which appears singly refractive.
Opticon An epoxy-like product used as a fracture filler.
Optivisors Plastic magnifying lenses attached to a headband.
Organic Gem Materials Gem materials which are partly or wholly comprised of animal or vegetable matter. Examples include pearl, amber, and coral.
Orientation Finding the best way of cutting a gemstone to maximize its best optical qualities, such as chatoyancy, luster, or inclusions.
Ornamental Stone Decorative materials which are usually softer, more opaque, more massive, more common, or less durable than hard translu cent or transparent gem materials, but are used for vases, bowls, carvings, bookends, clock faces, etc.
Oxalic Acid A few crystals can be added to the polish slurry of hard-to-polish gems.
Oxidation In jewelry, the chemical union of oxygen and metal which causes darkness or tar nish.
Oxidizing Flame A torch flame which used too much oxy gen and causes oxide films on metal.
Oxy-acetylene Torch A torch which burns acetylene gas and oxygen
P
Palladium A silvery white metal used in alloys and electroplating.
Pallions Small squares of solder.
Parting Plane The separating plane of a twinned crystal.
Patina Surface appearance of naturally or artifi cially aged metal, especially copper, brass, or silver.
Phenolic Lap A resin polishing lap used especially for hard stones.
Pavé A method of setting multiple stones in jewelry so little or no metal shows around the stones.
Pavilion The portion of a faceted stone below the girdle.
Pear Cut A gem cut with a rounded top and narrow ing down to a point.
Pearl Cement A durable cement used for pegging pearls.
Pebble Mosaic A picture or pattern composed of small rounded stones which are cemented onto a base and then grouted.
Pegmatite Magmatites with large, individual crystals; a source of many gem minerals.
Pellon A plasticized cloth used for the surfaces of polishing laps.
Pennyweight Precious metals such as gold wire are sold by the pennyweight, 24 grains troy.
Pewter An alloy composed of tin, antimony, and copper.
Phenomenal Stones Gem materials which have an unusual optical quality such as chatoyance, labra dorescence, asterism, etc. Pickle An acid bath for metal to dissolve surface oxidation and flux residue. Works more rapidly when heated in the pickle pot.
Piercing Making a design by cutting through the metal.
Piezoelectric Characteristic of some crystals that become electrically charged when mechanically altered.
Pitch A black semi-hard substance, which soft ens when heated, used in bowls to hold metal in place while it is being worked in such process as chasing or engraving.
Pitch Lap A scored lap made of opticians pitch, used for polishing large surfaces.
Planishing Hammering metal on a metal stake with a special hammer to remove irregularities.
Plastic Pellets Used as a filler and carrier in tumblers.
Plating Solutions Sulfate- or chloride-based solutions used for electroplating.
Play of Color The spectral colors which are seen in an opal as it is moved in changing light.
Pleochroism The quality of a gem to exhibit different col ors when viewed from several directions.
Pliers Pliers necessary for silversmiths are round nose, needle nose, flat nose, and cutting nose.
Plique-à-jour Enamel work on lacy metal frame such as filigree, which has no backing in part and this is transparent or translucent.
Pneumatic Scribe A small, air-driven, reciprocating impact tool used in the preparation of fossils.
Polish The smooth, glassy reflecting surface of a finished stone.
Polishing Agents The finely ground powders mixed with water for a polish slurry. (Sometimes formed as bars.) Examples include tin oxide, cerium oxide, and chrome oxide.
Preform A stone which is shaped to the approxi mate size and form desired but has not been fully ground and has not been sanded or polished.
Prepolish A satiny appearance which begins when the fine sanding is satisfactory.
Prestolite Torch A portable acetylene torch for jewelry work.
Prong Metal projection for holding stones in set tings.
Prong Pusher A tool with a blunt end for pushing prongs over stones.
Propane Torch Portable pinpoint torch which burns propane.
Pro-Slicer Blades Very thin blades for cutting high-quality gem material.
Pulley A grooved wheel attached to a motor shaft and machine shaft which transfers power from motor to machine by means of rub ber belts.
Pumice A fine powder for polishing or cleaning.
Punches Used with dapping blocks to shape metals.
Pyroelectric A characteristic of some minerals that become electrically charged when heated or cooled.
Pyrometer Device for measuring temperature in burn out ovens
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Rabbit Ear Bails Split top bails for pendants.
Raising Shaping metal with a hammer and a base.
Rapid Polish 61 A polish compound used for jade and hard to-polish stones.
Rathburn Saw Small jeweler’s saw with no V joint, used for sawing tubing.
Rawhide Mallet Leather mallet embedded with shellac for delicate metal work.
Raybrite A series of uniform micron-sized alumina polishes for stones of various hardnesses . Recirculating Pump Small pump to bring water to a grinding wheel.
Reducing Flame A properly adjusted flame for soldering has a blue tip and yellowish or greenish interior cone.
Reflection Light which reaches the eye when the beam strikes the surface of a gem. (Total reflection includes light from within.)
Refraction The bending of light rays that enter trans parent material.
Refractive Index A measure of the angle at which a light ray is deflected in a specific gem species.
Relief Carving Carving attached to and raised from the background. Replica Casting Instead of a lost wax model, a natural object such as a flower is burned out for the casting mold.
Repoussé A process of giving a sculptured effect to jewelry by hammering embossing tools onto the metal placed in a pitch bowl.
Reticulation Texturing metal into a deeply ridged sur face by the use of a torch.
Rheostat Control Speed control device for flexible shaft machines.
Rhodium Plate This metal, which is resistant to oxidation and acid, is often used to plate silver.
Ring Gauge Used to find the size or half-size for a ring.
Ring Mandrel Round, tapered steel stick for forming rings.
Rough Minerals or mineral aggregates which occur without a regular crystal surface, or gem material that has not been worked on.
Rough Grind The first grinding of the preform.
Rubber Mold A mold made of a special rubber which is used to make multiple identical castings.
Rutile Elongated needles of this mineral are com mon inclusions in many gems and are often responsible for sagenite and aster ism.
Ring Stick A tapered stick for measuring the size of a finished ring.
Ring Stretcher A tool which stretches the metal of a ring by thinning or rolling the metal.
Rivets So-called “cold connectors” for some jewelry items are rods slid through holes and flattened over the ends to hold parts together.
Rolling Mill A mill with steel rollers to alter the gauge of flat metal or wire, such as reducing thickness of metal or flattening wire.
Rondelle A polished metal disc used between beads in necklaces.
Rose Cut An early facet style with a flat bottom and round, domed faceted top made up of tri angle cuts coming to a point on top. Rotary Tumbler A machine which finishes gem materials when charged with appropriate grits and rolled over and over by an electric motor.
Rotary Wheel Dresser A rod tipped with carbon steel wheels for smoothing grinding wheels which are not true.
Rouge Various iron oxide powders used for polishes.
Sand Blaster A machine which forcefully blows out streams of grits of various hardnesses to abrade, texturize, etch, or carve gem materials.
Sand Casting An old method of casting with wet casting sand being pressed firmly around the model making a mold for filling with molten metal.
Sander A disc or belted charged with abrasives which smooth the surfaces of stones, pre paring them for polishing.
Sanding Cloth The cloth belt or disc which is charged with abrasives for the sanding processes between the grinding and polishing steps.
Satin Finish A smooth but not brilliant metal polish.
Saw Speed The revolutions per minute and the surface feet per minute of a revolving saw blade.
Scale Oxidation of a metal surface caused by heat.
Scarab A cabochon engraved with a variation of the ancient Egyptian sacred beetle design.
Schiller A metallic-appearing shimmer or sheen seen in some gem materials.
Scoring Cutting radial lines in soft metal faceting laps to prepare the lap for polishing large facets.
Scotch Stones Slatelike stones used with water for remov ing blemishes on a metal surface.
Screw Feed A threaded metal bolt which feeds the material by turning to push the carriage of the slab saw forward.
Scribers Sharp tools used to draw or trace designs on metal.
Scroll Work Jewelry made with soldered scrolls of wire.
Sculpt-Wire Clay-like substance which air-hardens to a metallic mass similar to “liquid steel.”
Selvyt Cloth A flannel jewelry polishing cloth, half charged with rouge. Serpentine Chain Identical flattened “s” shaped links.
Sgraffito An enamel technique with a design scribed through to expose previously fired layers.
Shaft The steel rod upon which the revolving parts are mounted.
Shellac Used to dop sensitive stones or to make abrasive tools.
Shepherd Hooks Hook-shaped earwires.
Silicon Carbide Carborundum. A hard synthetic for grind ing and sanding.
Sinking Forming metal by pounding and stretching it into a hemispherical die.
Sinter Mineral deposit in springs.
Sintered Rim Blade A saw blade with diamond powder mixed with metal powder and made into a thin circle, which is then heat treated and sol dered to the edge of a circular saw.
Slab A flat section or slice of rock.
Slab Saw A saw which is designed to cut slabs or slices of rough material with a circular dia mond saw blade.
Slabsorbe A liquid for removing oil from slabs.
Slurry The mixture of polishing powder and water used on a polishing buff.
Soft Stone A stone less than 5 in hardness on the Mohs scale.
Solder A variety of alloys, mostly gold or silver, which when heated to the flowing point will permanently unite the chosen pieces of metal.
Soldering Blocks Soldering is done on a fire-proof block such as charcoal, fire brick, or ceramic. Sparlike Aggregates having characteristically smooth, often shiny, cleavage faces.
Specific Gravity The density of a mineral in comparison to that of water. Sphere Machine A machine used to shape and polish spheres by the use of revolving cutters and various grits.
Spindle A tapered, threaded tool to hold buffs.
Spinning Forming metal by stretching it over a chuck using a lathe.
Splash Hood The cover for a slab saw which prevents coolant mist from spraying into the room.
Splash Pan A metal pan beneath the grinders and sanders to catch water.
Splash Shield The metal hood above the grinding and sanding wheels designed to keep water from splashing into the room or onto the lapidary.
Spool Sander A grooved, curved wooden machine for sanding cabochons.
Spring Ring A ring-shaped jewelry clasp with a spring in the tube.
Sprue That part of the wax model which reaches to the edge of the flask so that when it melts there will be a canal for the molten metal.
Sprue Base Base for attaching the sprue to the model.
Sprue Wax Wax rod for making sprues which will burn out cleanly and quickly.
Stakes Smooth steel forms for use in forming, rais ing, and planishing metals with hammers.
Stamps Steel tools for stamping impressions into metal surfaces.
Standard Brilliant Round 58 facet gem.
Star Facets Triangular facets next to the table.
Steam Casting An inexpensive method of casting using steam pressure.
Step Cut Emerald cut. A basic facet design, usually rectangular or square, with rows of parallel facets
Sterling A standard of metal purity for silver with 75/1000 parts of copper to 925/1000 parts of fine silver.
Stone Holder A movable pronged holder for inspecting faceted stones.
Stripping Removing scale, old plating, or dull surface of metal by electrolysis.
Swage Block A block with various sizes of indentations to hold tubing for sawing and filing.
Swedish Files Small needle files
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Table The flat facet on the top of a faceted gem.
Tang The end of a graver or file which fits into the handle.
Tank Reservoir. The pan for holding the coolant/ lubricant of a slab saw.
Taps Metal taps with matching dies are used for threading items such as ear screws.
Template Sheets of plastic or metal with cutouts of various sizes and shapes of cabochons for outlining on stone.
Tensile Strength The property of a metal to be stretched without tearing apart.
Third Hand A stand for holding items to be soldered.
Thrumming Buffing inaccessible areas with a string or cord.
Tiffany Mount A prong setting for a faceted stone mounted on top of the ring shank, allowing more light.
Tiger Tail Nylon-coated bead wire.
Tin Lap A soft metal lap used for faceting.
Tin Oxide A popular polishing powder.
Titanium Lightweight refractory metal used for con temporary jewelry.
Torpedo Clasp Also barrel clasp. Metal parts screw together for a lock.
Toughness The property of structural particles of a gem material to cling together to avoid breakage.
Transfer Block Also transfer jig. The block which makes it possible to align dopsticks for transferring a gem being faceted.
Translucent Gem material which transmits light but is not clear enough to see through.
Transparent Gem material in which the interior can eas ily be seen and which one can see through when it is held to the light.
Tri-Color Gold Jewelry made with three colors of gold — yellow gold, rose gold, and green gold (usually).
Tri-Cord Knotter A device for making quick, uniform knots in necklaces of pearls or other beads.
Trilliant A modern, curved triangular brilliant cut, originally 44 facets.
Trim Saw An electric saw for rough shaping of cabo chon blanks from slabs of gem material.
Tripoli Silicon dioxide polishing powder.
Trivet A metal stand used to hold work during the process of fusing (such as enamel) to metal.
Troy Weight System of weight for precious metals. One troy ounce equals 1.10 avoirdupois ounces.
Tubing Formed by pulling a metal strip through a drawplate and used for hinges, clasps, and links.
Tufa Porous rock formed as a deposit from springs or streams.
Tumbler A rotary or vibratory machine which will produce finished stones from tumbling rough.
Tumbler Charges Measured grits, powders, and some times additives used in the tumbling process
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Ultralap A plastic lap embedded with abrasive or polishing agents.
Ultrasonic Cleaners Machines filled with cleaning solution which vibrate at high frequencies.
Ultrasonic Drill A high-tech, fast-vibrating drill with elec tronically supplied abrasives.
Undercut The property of some fibrous or granular gems to develop small pits during sanding and/or polishing.
Uniaxial Stones with one optic axis.
V
Vacuum Casting A system of casting with a machine which pulls air and gases from the mold so that molten metal will flow quickly.
V-Dop A dop stick with a “V” notch for elongated stones.
Vermeil Gold-plated sterling silver
Vernier An auxiliary gauge for a millimeter slide gauge for determining gem depth; a sec ondary gauge to subdivide small units on the primary gauge.
Vibralap Automatic flat lap for processing flats by vibrating.
Vibratory Tumbler Rapidly vibrating tumbler with unusually upright hoppers, many of which are open.
Vibro-Graver A vibrating electric engraving machine with adjustable stroke.
Vise The part of the saw that holds the rock being cut. It often has hardwood jaws
W
Water-Soluble Wax Wax used as a foundation for building a wax model for a piece of jewelry which will appear heavy or bulky but will actually be quite thin. The foundation wax is dissolved before the casting.
Wax Lap A lap coated with wax for polishing soft materials.
Wax Pen An electric pen for making wax models that keeps the wax melted, to be released through a trigger tip.
Wax Pot Electric pot for keeping wax at the proper temperature for making models for casting.
Wax Wire Round wax wires of different gauges, which can be twisted and bent into designs for wax jewelry models.
Wet Belt Sander Complete, ready-to-use sander for cabs and flats.
Wet-or-Dry Belts Silicon carbide sanding belts.
Wheel Cement A bonding agent for abrasive discs or pol ishing pads.
White Diamond A fine tripoli polish.
White Oil A preferred cutting oil for slab saws.
Winding Jig Metal or hardwood jig with wire protru sions for winding filigree wire into intricate designs, which are then removed from the jig by a lifting plate.
Wire Saw An iron, diamond-charged saw blade, straight rather than circular.
Work Hardened Metal which has been worked gets increasingly harder, so that it must be annealed to maintain its workability.
Y
Yellow Ochre A solution that is painted on jewelry parts that need to be kept cool during soldering
Z
Zam A buffing compound similar to rouge.
Zinc Lap A faceting lap for corundum.
Zirconium Oxide A polishing agent similar to cerium oxide.
