Bench terminal
Materials glossary
206 materials a jewelry or eyewear listing can name, grouped by what kind of thing each is: metals and alloys, platings, stones (natural, lab-grown and simulant), organics, glass, findings, lens materials and coatings, frame materials, and the standards and marks behind the words. Every entry says what the thing is and where the public record on it is (Wikidata, PubMed); none values a piece or promises anything about your skin or eyes.
AllMetalAlloyPlating and finishGemstoneLab-grown and simulantOrganic materialGlass, crystal and resinFinding and chainLens materialLens coatingFrame materialStandard and mark
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10-karat gold10k gold · Metal41.7 percent gold (417 fineness), the lowest purity that may legally be sold as gold in the United States. Durable and paler; more copper…14-karat gold14k gold · Metal58.3 percent gold (585 fineness). The most common US fine-jewelry alloy: hard enough for daily rings, less yellow than 18k, and the usual…18-karat gold18k gold · Metal75 percent gold (750 fineness), the rest silver, copper, zinc or palladium. The usual fine-jewelry standard in Europe; warmer in color and…
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A
Abalone (paua)Organic materialThe iridescent shell of abalone, cut for inlay and pendants; same care as pearl.AcrylicGlass, crystal and resinA hard clear plastic (PMMA) used for inexpensive beads, 'lucite' and lightweight statement pieces; scratches easily, can be polished.AgateGemstoneBanded chalcedony (microcrystalline quartz) in many colors, Mohs 6.5 to 7; bright pinks, blues and greens are dyed.Akoya cultured pearlAkoya pearl · Organic materialSaltwater pearls from Japan and China, bead-nucleated, round, with the brightest luster; 6 to 9 mm, white with rose or cream overtones.AlexandriteGemstoneChrysoberyl that changes from green in daylight to red under incandescent light; rare and costly when natural. Lab-grown alexandrite shows…AluminumMetalLight, soft, does not rust; anodized aluminum takes bright colors. Used in lightweight earrings and some frames.AmberOrganic materialFossilized tree resin, Mohs 2 to 2.5, warm to the touch and light enough to float in salt water. Baltic amber is the common source;…AmethystGemstonePurple quartz, the February birthstone, Mohs 7. Affordable because large clean crystals are common; fades slowly in strong sun over years.ANSI Z80.3Standard and markThe US standard for non-prescription sunglasses: UV transmission limits, impact resistance, optical quality. Lenses sold as UV400 or '100%…Anti-reflective (AR) coatingAnti-reflective coating · Lens coatingThin layers on the back of a sunglass lens that stop light bouncing into the eye from behind, and on clear lenses reduce reflections and…AppraisalStandard and markA written valuation for insurance by a graduate gemologist; a paid document, and not the same as a grading report (GIA, IGI), which…AquamarineGemstoneBlue to blue-green beryl, the March birthstone. Mohs 7.5 to 8, usually clean and light in color; most are heated to remove green.Argentium silverAlloyA sterling alloy with germanium replacing part of the copper, which slows tarnish and makes the surface harder. Still 925 or 935 silver.Austrian crystalGlass, crystal and resinPrecision-cut glass crystal in the Swarovski tradition; a glass simulant with a foil or coated back for brightness.AventurineGemstoneGreen quartz with mica flecks, Mohs 6.5 to 7; often sold as 'Indian jade'.
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BailFinding and chainThe loop on a pendant that the chain passes through; a hinged bail lets a pendant go on an existing necklace.Bezel settingFinding and chainA metal rim that wraps the stone's edge; the most protective setting, slightly dims the stone, and the usual choice for soft stones and…Bifocal readerLens materialA clear or tinted lens with a magnifying segment at the bottom, so distance stays clear above it.Black rhodiumPlating and finishRhodium plating with additives that give a dark grey finish; wears to the base color at edges with time.Blue-light-filtering lensBlue-light lens · Lens materialA clear lens with a coating or dye that cuts part of the 400 to 450 nm band; studies of its effect on eye strain or sleep are mixed, and…BoneOrganic materialCarved bovine bone, cream-colored with a fine grain; often sold as 'ox bone'. Softer than horn and stains easily.Box chainFinding and chainSquare links that make a smooth rope; strong and does not kink.Box claspFinding and chainA folded tongue that snaps into a box, often with a safety catch; the usual clasp on tennis bracelets and good watch bands.BrassMetalAn alloy of copper and zinc, yellow and often used as the base for plated jewelry. Tarnishes and can green the skin when the plating wears;…BronzeMetalAn alloy of copper and tin, browner than brass. Used in cast jewelry and some watch cases; develops a patina.Butterfly (friction) backButterfly back · Finding and chainThe folded-metal catch that slides onto a post; loosens with wear and is the most-lost earring part.
C
Cable chainFinding and chainRound or oval links each through the next; the plain, strong, repairable chain.Carat (ct)Standard and markThe weight unit for gemstones: 0.2 grams. Not karat; a 1 ct diamond weighs a fifth of a gram.CarnelianGemstoneOrange-red chalcedony, Mohs 6.5 to 7; most is heated or dyed to even the color.Category 3 lensLens materialThe common sunglass darkness (8 to 18 percent of light passes); category 4 is for glacier and sea use and is not legal for driving.CE mark (EN ISO 12312-1)Standard and markThe European sunglass standard, which also sets lens categories 0 to 4; a CE mark on US-sold sunglasses means the maker claims that test.Cellulose acetateFrame materialA plant-based plastic (cotton and wood pulp) cut from colored sheets; the material of quality plastic frames: rich colors, adjustable with…ChalcedonyGemstoneMicrocrystalline quartz in soft blues and greys; Mohs 6.5 to 7; often dyed.Channel settingFinding and chainStones held between two metal walls in a row; the usual setting on eternity bands, which cannot be resized.ChrysoberylGemstoneA hard (Mohs 8.5) yellow-green stone; cat's-eye chrysoberyl shows a sharp moving line.CitrineGemstoneYellow to orange quartz, a November birthstone. Most commercial citrine is heat-treated amethyst, which is standard and should be disclosed.Cobalt chromeMetalAn alloy of cobalt and chromium used for men's bands: white, bright, harder than platinum, cannot be resized by most jewelers. Cobalt is a…Conflict-freeStandard and markA claim that a diamond was not mined to fund armed conflict, under the Kimberley Process; it covers rough diamond origin, not labor…CopperMetalElement 29, a soft reddish metal. Worn on its own in bracelets and used in most gold and silver alloys. Reacts with skin acids to leave a…CoralOrganic materialThe calcium carbonate skeleton of certain corals, red to pink; Mohs 3 to 4. Precious red coral is CITES-regulated and most 'coral' in…CR-39 (plastic) lensLens materialThe standard plastic lens since the 1940s: clear, light, cheap, better optics than polycarbonate and easier to scratch. Blocks most UVB but…Created gemstoneLab-grown and simulantThe FTC-accepted term for a lab-grown stone with the same chemistry as the natural one. 'Created' never describes a simulant.Crystal (leaded glass)Glass, crystal and resinGlass with lead oxide (or, in newer 'lead-free crystal', barium or zinc) for extra sparkle and weight; Swarovski-type stones are…Cubic zirconia (CZ)GemstoneSynthetic zirconium oxide, the standard diamond simulant since the 1970s: Mohs 8 to 8.5, more fire than diamond, colorless, and…Curb chainFinding and chainFlattened, interlocking links that lie flat; Cuban link is a thick curb chain.
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E-coat (electrophoretic lacquer)Plating and finishA clear lacquer baked over plated brass to slow tarnish and skin contact; wears off at edges and cannot be repaired.Earring postFinding and chainThe straight wire of a stud; by US practice 20 gauge (0.8 mm). Posts are the part that touches the piercing, so their metal matters most…ElectrumAlloyA natural or made alloy of gold and silver, pale yellow; the metal of the first coins and of some artisan pieces.EmeraldGemstoneGreen beryl colored by chromium or vanadium. Mohs 7.5 to 8 but brittle and almost always included; most are oiled to hide fractures, which…EnamelPlating and finishPowdered glass fused onto metal at high heat (vitreous enamel), or a cold resin colored to imitate it. Vitreous enamel is hard and…Extender chainFinding and chainThe extra inch or two of chain at the clasp that lets a necklace be worn at two lengths.
F
Fairmined goldFair-mined gold · Standard and markGold from certified artisanal mines paying a premium to the community; a third-party label (Fairmined, Fairtrade Gold).FDA impact test (21 CFR 801.410)FDA drop-ball test · Standard and markThe US rule that all eyeglass and sunglass lenses must survive a 5/8-inch steel ball dropped from 50 inches; plastic lenses pass by…Figaro chainFinding and chainA pattern of three small links and one long one; the Italian men's chain standard.Fine silver (999)Metal99.9 percent silver. Used for bezels and some handmade pieces because it is easy to work; it bends and marks easily and tarnishes more…Fineness (925, 750, 585)Standard and markPurity in parts per thousand, the European and silver convention: 925 is sterling, 750 is 18k, 585 is 14k, 950 is platinum.Flash mirror coatingLens coatingA light mirror coating that adds color without cutting much light.Flash platingPlating and finishPlating under about 0.2 microns, enough for color and no more; the thinnest commercial layer, common on costume pieces.FluoriteGemstoneCalcium fluoride in purple, green and bands, Mohs 4: a display and pendant stone, too soft for rings.French hook (fish hook)Finding and chainAn open curved wire with no closure; light and easy to put on, easy to lose without a rubber stopper.Freshwater cultured pearlFreshwater pearl · Organic materialPearls from mussels in Chinese lakes, tissue-nucleated so they are nearly all nacre; the affordable, durable pearl in most jewelry, in…FTC Jewelry GuidesStandard and markThe US Federal Trade Commission's rules for how jewelry may be described: when 'gold' needs a karat, what 'gold-filled' and 'vermeil' mean,…
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GarnetGemstoneA family of silicate minerals, Mohs 6.5 to 7.5: deep red almandine and pyrope are the common January birthstone; green tsavorite and orange…GlassGlass, crystal and resinSoda-lime or lead glass cut or molded into beads and stones; Mohs 5.5, scratches, and the honest material of most costume jewelry.Glass (mineral) lensGlass lens · Lens materialCrown glass: the clearest and most scratch-resistant lens, and the heaviest; it can shatter, so US glass lenses must be tempered to pass…GoldMetalA soft yellow metal, element 79. Pure (24k) gold is too soft for daily wear, so jewelry gold is an alloy; the karat number says how many…Gold platedPlating and finishA layer of gold electroplated onto a base metal (brass, copper, steel, silver). No legal minimum thickness in the US for the words 'gold…Gold-filled (GF)Gold filled · Plating and finishA thick layer of karat gold mechanically bonded to a base (usually brass); by US rule the gold must be at least 1/20 (5 percent) of the…Gradient lensLens materialA tint darker at the top than the bottom, for driving (sky dark, dashboard clear); the UV rating is separate from the tint.Grading reportStandard and markA laboratory's description of a diamond or gemstone (GIA, IGI, GCAL): weight, measurements, color, clarity, cut, and whether it is natural…Green goldAlloyGold alloyed with silver alone, which gives a pale greenish tint; uncommon, used for leaves and accents.
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HallmarkStandard and markAn official assay-office stamp guaranteeing purity, required in the UK and some countries; the US has no hallmarking system, only the…Heavy gold electroplate (HGE)Plating and finishGold plating at least 2.5 microns thick under the FTC Jewelry Guides; lasts years with care rather than months.HematiteGemstoneIron oxide, metallic grey-black and heavy, Mohs 5.5 to 6.5. 'Magnetic hematite' is a made ferrite, not the mineral.High-index lensLens materialPlastic lenses that bend light more, so strong prescriptions can be thinner; a prescription matter, not sold here.HornOrganic materialKeratin from cattle or buffalo, dark and translucent at the edges; light, warms to the skin, and warps in heat.HowliteGemstoneA white, veined borate mineral, Mohs 3.5, that dyes easily; the usual material behind cheap 'turquoise' and colored 'magnesite' beads.HuggieFinding and chainA small hinged hoop that snaps closed and sits against the lobe.Hydrophobic (oleophobic) coatingHydrophobic coating · Lens coatingA top layer that sheds water and fingerprints so the lens cleans with a wipe.HypoallergenicStandard and markA marketing word with no legal standard in US jewelry; it usually means nickel-free or made of titanium, niobium, platinum or surgical…
I
Injection-molded plastic (TR90, nylon, polycarbonate)Frame materialFrames molded in one shot, light and flexible, cheaper than acetate, in flat colors; TR90 is a nylon that bends without breaking.IoliteGemstoneBlue-violet cordierite, Mohs 7 to 7.5, strongly pleochroic (different colors from different angles). Untreated.Ion plating (IP)Plating and finishA form of PVD used on steel watches and jewelry; the same vacuum process, marketed under another name.IvoryOrganic materialElephant ivory is banned from sale in the US with narrow antique exceptions; 'ivory' in fashion jewelry is bone, resin or tagua nut…
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JadeGemstoneTwo minerals: jadeite (the rarer, Burmese) and nephrite (the tougher, Chinese and New Zealand). Mohs 6 to 7 and the toughest gem material.…JetOrganic materialFossilized wood, black and very light, Mohs 2.5 to 4; the Victorian mourning-jewelry material. 'French jet' is black glass.Jump ringFinding and chainThe small wire ring that joins parts. Open (unsoldered) rings are the weak point on most chains; soldered rings do not pull open.
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Karat (k, kt)Standard and markThe US purity scale for gold: parts of gold in 24. 24k is pure, 18k is 75 percent, 14k is 58.3, 10k is 41.7 (the legal minimum to be sold…Keyhole bridgeFrame materialA bridge shaped like a keyhole that rests on the sides of the nose; suits narrow or low bridges.KunziteGemstonePink spodumene, Mohs 6.5 to 7; fades in sunlight and cleaves, so an evening stone.
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Lab-created emeraldLab-grown emerald · Lab-grown and simulantHydrothermally or flux-grown beryl; same chemistry, far fewer inclusions and lower price than natural.Lab-created opalLab-grown opal · Lab-grown and simulantSynthetic opal with a regular, 'lizard skin' play-of-color pattern; more stable than natural opal.Lab-created rubyLab-grown ruby · Lab-grown and simulantSynthetic red corundum; the same chemistry as natural ruby, inexpensive, and often the 'ruby' in class rings.Lab-created sapphireLab-grown sapphire · Lab-grown and simulantCorundum grown by flame fusion or other methods, the same material as natural sapphire; used in watch crystals and jewelry. Must be…Lab-grown diamondLab-grown and simulantCrystalline carbon grown by HPHT or CVD methods; chemically and optically the same as mined diamond, Mohs 10, and told apart only with lab…LabradoriteGemstoneFeldspar with flashes of blue, green and gold (labradorescence); Mohs 6 to 6.5. Untreated.Lampwork glassGlass, crystal and resinGlass beads formed by hand over a torch; each one differs, and the holes can have sharp edges that cut cord.Lapis lazuliGemstoneA rock, not a mineral: lazurite with pyrite flecks and calcite. Mohs 5 to 5.5, porous, often dyed to deepen the blue.Lead in jewelryStandard and markLead and cadmium turn up in cheap cast metal and in some enamel and crystal; US federal law limits lead in children's jewelry to 100 ppm,…Lead-glass-filled rubyLab-grown and simulantLow-grade corundum with its fractures filled with lead glass to make it transparent; fragile, damaged by heat and household chemicals, and…LeatherOrganic materialCord and wrap bracelets; 'genuine leather' is the lowest grade, full-grain the best.Lever backFinding and chainA hinged hook that snaps closed behind the lobe; secure for drop earrings.Lobster claspFinding and chainA spring-loaded hook-shaped clasp opened with a tiny lever; the most secure common clasp and the easiest to replace.
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Magnetic claspFinding and chainTwo magnets that meet; convenient for stiff fingers, weak for heavy pieces, and the CPSC has recalled children's jewelry with loose magnets…MalachiteGemstoneBanded green copper carbonate, Mohs 3.5 to 4: soft, scratches easily, and its dust is toxic, so keep it off cut skin and away from acids…Memory metal (Flexon, nitinol)Frame materialA nickel-titanium alloy that springs back after bending; nickel is bound in the alloy and rarely a problem, but it is present.Memory wireFinding and chainSteel wire that holds its coil shape, used for wrap bracelets with no clasp; contains nickel.Metal frameFrame materialFrames of stainless steel, monel, titanium or aluminum; monel (a nickel-copper alloy) is common in cheap metal frames and the usual cause…Mirrored lensMirror lens · Lens materialA reflective metal coating on the outside that cuts the light entering and hides the eyes; the UV blocking comes from the lens beneath, not…Mohs hardness scaleMohs scale · Standard and markA 1 to 10 ranking of what scratches what: talc 1, quartz 7, topaz 8, corundum 9, diamond 10. Stones under 7 are scratched by household dust…MoissaniteLab-grown and simulantSilicon carbide, grown in a lab (natural moissanite is vanishingly rare). Mohs 9.25, more fire than diamond and a slightly different…Mokume-ganeAlloyLayers of different metals forged and twisted into a wood-grain pattern; a technique, not a single metal, so the layers' metals matter for…MonelFrame materialA nickel-copper alloy used in inexpensive metal eyeglass frames; strong and bendable, high in nickel.MoonstoneGemstoneFeldspar that shows a floating blue or white sheen (adularescence). Mohs 6 to 6.5, cleaves; rainbow moonstone is a labradorite.MorganiteGemstonePink to peach beryl; the pink is often strengthened by heat. Mohs 7.5 to 8.Mother-of-pearlMother of pearl · Organic materialThe nacre lining of the shell, cut into flat pieces for inlay, dials and beads; same material as pearl, same care.Murano glassGlass, crystal and resinHand-worked glass from the Venetian island, often with gold leaf or millefiori canes; much 'Murano' sold cheaply is Chinese lampwork.
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Nickel allergyStandard and markThe most common contact allergy: about 10 to 20 percent of women and a few percent of men react to nickel with an itchy rash where metal…Nickel silver (German silver, alpaca)AlloyAn alloy of copper, nickel and zinc that contains no silver at all. Silver-colored, cheap, and the most common source of nickel reactions…Nickel-freeStandard and markA claim with no US legal definition; in the EU it means the piece releases under 0.5 micrograms of nickel per square centimetre a week by…NiobiumMetalA grey refractory metal that can be anodized to blue, purple and gold without dye. Nickel-free and used for hypoallergenic ear wires and…Nose padsFrame materialSilicone pads on metal frames that can be swapped; acetate frames have molded pads that cannot.Nylon (polyamide) lensNylon lens · Lens materialA light, flexible plastic used in wraparound sport sunglasses; good optics and impact resistance.
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ObsidianGemstoneNatural volcanic glass, black or banded, Mohs 5 to 5.5; sharp-edged when broken and easily scratched.OnyxGemstoneBanded chalcedony; the solid black jewelry onyx is almost always dyed agate, which is traditional and legal when described as onyx. Mohs…OpalGemstoneHydrated silica that diffracts light into play-of-color. Mohs 5.5 to 6.5 and contains water, so it cracks with heat and dryness; doublets…Oxidized (antiqued) silverOxidized silver · Plating and finishSterling deliberately darkened with a sulfide solution to shadow the recesses; the raised surfaces polish bright with wear.
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PalladiumMetalElement 46, a platinum-group metal: white, light, does not tarnish. Used on its own (950 palladium) and as the whitening metal in…Paperclip chainFinding and chainLong oval open links; the fashion chain of recent years, light for its size.Pavé settingFinding and chainMany small stones set close together with tiny beads of metal; sparkles, and sheds stones if the piece is knocked or the metal is thin.PearlOrganic materialNacre (calcium carbonate and protein) laid down by a mollusk. Almost all pearls sold are cultured (a bead or tissue nucleus is implanted);…PeridotGemstoneGem olivine, yellow-green, the August birthstone; Mohs 6.5 to 7, so better in earrings and pendants than daily rings. Never treated, which…PewterMetalA tin alloy, soft and grey, used for cast charms and pendants. Modern pewter is lead-free by law in jewelry; older pieces may not be.Photochromic lensLens coatingA lens that darkens in UV light and clears indoors (Transitions is a brand); slow to clear in cold, and does not darken much behind a car…PlatinumMetalElement 78, a dense white metal that does not tarnish. Jewelry platinum is usually 950 (95 percent) or 900; it is heavier than gold,…Polarized lensLens coatingA film inside or on the lens that blocks horizontally reflected light, the glare off water, snow and roads. Does not add UV protection;…Polycarbonate lensLens materialA tough, light plastic lens that blocks UV to 400 nm by itself and passes impact tests, which is why it is the standard for sports, safety…Polymer clayGlass, crystal and resinPVC clay baked hard; the material of handmade earrings in every color. Light, does not shatter, softens in a hot car.PrehniteGemstoneA translucent yellow-green silicate, Mohs 6 to 6.5; inexpensive and untreated.Progressive lensLens materialA lens with a gradual change from distance to reading power, no visible line; a prescription item in most cases.Prong (claw) settingProng setting · Finding and chainMetal claws that hold a stone from the side so light enters from below; the standard for diamonds. Prongs wear and should be checked yearly.Proposition 65Standard and markCalifornia's law requiring a warning on products that can expose users to listed chemicals, including lead, cadmium and nickel compounds;…PVD coatingPlating and finishPhysical vapor deposition: a hard, thin metal or ceramic film (often titanium nitride for gold color) bonded in a vacuum chamber. Much…
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Reader (plus) lensReading lens · Lens materialA single-vision magnifying lens in strengths from +0.75 to +4.00 diopters; the same in both eyes on off-the-shelf readers.Reader strength (diopter)Standard and markThe power of a reading lens in diopters, +1.00 to +4.00 in steps of 0.25; higher means closer focus. Off-the-shelf readers use the same…Recycled goldStandard and markGold refined from old jewelry, electronics or industrial scrap rather than newly mined; chemically identical. Certified by schemes such as…ResinGlass, crystal and resinCast epoxy or polyester plastic, clear or colored, often with flowers or glitter inside; light, scratches, yellows in sun over years.RhinestoneGlass, crystal and resinSmall faceted glass (or acrylic) stones with a mirrored back, glued or prong-set; the sparkle of costume jewelry.RhodiumMetalA platinum-group metal, very white and hard, used only as plating (it is too brittle to form). The bright white on most white gold and…Rhodium platedPlating and finishA thin rhodium layer that gives sterling and white gold a bright white, tarnish-free surface. Wears through in one to three years on rings…Ring sizeStandard and markThe inside circumference of a ring, expressed as a US number (3 to 15), a UK letter or the ISO millimetre measure; the converter on this…Rope chainFinding and chainTwisted strands of small links; the classic look for men's chains and the most prone to kinking.Rose goldAlloyGold alloyed with a high share of copper, which gives the pink. 14k rose gold is 58.3 percent gold; the copper makes it slightly harder…Rose quartzGemstonePink quartz, Mohs 7, usually cloudy; untreated and inexpensive.RubyGemstoneRed corundum, the same mineral as sapphire, colored by chromium. Mohs 9. Heat treatment is routine; glass-filled rubies (lead glass in…
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SapphireGemstoneCorundum (aluminum oxide) in any color but red; blue is classic. Mohs 9, so suited to daily rings. Most sapphires are heat-treated, which…Scratch-resistant hard coatLens coatingA clear hardened layer on plastic lenses; makes them scratch less, not scratch-proof.Screw backFinding and chainA threaded post and nut; the most secure stud back, common on children's and diamond studs.Sea glassGlass, crystal and resinBroken glass tumbled smooth by the sea; genuine pieces are frosted and rare in red and blue, and most 'sea glass' jewelry uses tumbled…ShakudoAlloyA Japanese copper-gold alloy that is patinated to a blue-black; used in mokume-gane and art jewelry.Shell pearlOrganic materialA bead of shell coated with a pearl-like lacquer; a simulant, not a pearl, and sold as such.Silk threadFinding and chainThe traditional stringing for pearls, knotted between each pearl so they do not rub; restring every few years of regular wear.SilverMetalElement 47, the whitest and most reflective metal. Pure silver is too soft for most jewelry and tarnishes in air (a sulfide film that…Silver platedPlating and finishA thin silver layer over base metal; tarnishes like silver and wears through to the base. Not sterling, and not stamped 925.Simulated diamondLab-grown and simulantAny stone that looks like diamond but is not carbon: cubic zirconia, moissanite, glass, white sapphire. Legal only when called a simulant…Smoky quartzGemstoneBrown to grey quartz, colored by natural or lab irradiation; Mohs 7.Snake chainFinding and chainTightly fitted plates or rings that make a smooth flexible tube; elegant, hard to repair once kinked.SodaliteGemstoneRoyal-blue silicate with white veins, Mohs 5.5 to 6; untreated.South Sea cultured pearlSouth Sea pearl · Organic materialLarge (9 to 20 mm) white or golden saltwater pearls from Australia, Indonesia and the Philippines; the costliest cultured pearls.SpinelGemstoneA magnesium aluminum oxide in red, pink, blue and black; Mohs 8, rarely treated, and the stone many historic 'rubies' turned out to be.…Spring hingeFrame materialA hinge with a spring that lets the temples open beyond 90 degrees; forgiving for taking glasses on and off one-handed.Spring ring claspFinding and chainA round clasp with a sprung pin; the oldest cheap clasp, fiddly for one-handed use and the first thing to fail on a thin chain.Stainless steelMetalAn iron alloy with chromium (and usually nickel) that resists rust. 316L (surgical) is the jewelry grade; it contains nickel, but bound so…Sterling silver (925)Alloy92.5 percent silver and 7.5 percent other metal, almost always copper. The jewelry standard for silver; stamped 925. Tarnishes to grey or…Stretch elastic cordStretch cord · Finding and chainElastic cord for beaded bracelets; the cheapest and least durable stringing, stretches out in a year or two.SunstoneGemstoneFeldspar with copper or hematite flakes that glitter; Oregon sunstone is the untreated US variety.Surgical stainless steel (316L)316L stainless steel · MetalThe low-carbon grade of 316 stainless used for implants and body jewelry. Contains 10 to 14 percent nickel in the alloy; it releases very…
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Tahitian cultured pearlTahitian pearl · Organic materialDark saltwater pearls from the black-lipped oyster in French Polynesia; grey, green, peacock, 8 to 14 mm.TanzaniteGemstoneBlue-violet zoisite from one area of Tanzania; almost all is heated from brown. Mohs 6 to 7 and cleaves easily; a pendant stone more than a…Tension settingFinding and chainA stone held by the spring pressure of the band alone; needs a hard metal and cannot be resized.Tiger's eyeGemstoneGolden-brown quartz with a silky chatoyant band, Mohs 7; some red tiger's eye is heated.Tinted lensLens materialDye in or on the lens that reduces visible light: grey keeps colors true, brown adds contrast, green is between, yellow brightens low…TitaniumMetalElement 22: light, strong, grey, does not corrode and is used in implants, so it is one of the safest metals for sensitive skin. It cannot…Titanium frameFrame materialLight, strong, nickel-free frames; beta-titanium bends, pure titanium holds shape. Costs more.Toggle claspFinding and chainA bar that passes through a ring and rests across it; easy to fasten, relies on the weight of the piece to stay closed, so not for light…TopazGemstoneAn aluminum silicate, Mohs 8. Natural topaz is mostly colorless or pale; the common blue (Swiss blue, London blue) is made by irradiating…TourmalineGemstoneA boron silicate in every color, Mohs 7 to 7.5; pink (rubellite), green and the rare neon Paraíba. Some pink stones are heated or…TR90Frame materialA Swiss-developed thermoplastic nylon used for light, flexible, nearly unbreakable sport and kids' frames.Trivex lensLens materialA lighter, clearer impact-resistant plastic than polycarbonate; blocks UV, costs more, used in rimless and safety frames.Tungsten carbideMetalA ceramic-metal compound of tungsten and carbon, the hardest material used for rings (about 9 on the Mohs scale). It does not scratch but…TurquoiseGemstoneA copper-aluminum phosphate, opaque blue to green, Mohs 5 to 6 and porous. Most commercial turquoise is stabilized with resin;…
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White goldAlloyGold alloyed with white metals (nickel, palladium, silver, zinc) to look silver-white, then usually plated with rhodium. Nickel white gold…WoodOrganic materialCarved or turned hardwood in beads, rings and frames; sealed with oil or lacquer, swells in water.Wood frameFrame materialLaminated hardwood or bamboo frames; light, each unique, and not adjustable with heat.
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Zinc alloy (pot metal)MetalCast zinc with aluminum, copper or magnesium, the base metal of most inexpensive fashion jewelry under its plating. Light, easy to cast,…ZirconGemstoneA natural zirconium silicate (not cubic zirconia), Mohs 6.5 to 7.5, with high brilliance; blue zircon is heat-treated. The December…
How to read a listing
The metal comes first: "14k gold" is solid; "gold-filled" is a thick bonded layer; "gold plated" or "gold tone" is a thin layer over brass or steel; "925" or "sterling" is solid silver. For stones, "created" or "lab-grown" means the real material made in a lab, "simulated" means a look-alike, and a color-only name ("emerald green") means glass or crystal. For lenses, UV400 is the protection claim and "polarized" the glare claim; the tint says neither.
Where the words come from
The groups follow the FTC Jewelry Guides and the GIA's material classes; the one-line descriptions are ours, written from the public record (FTC, GIA, USGS, ANSI). A Wikidata description and the three most recent PubMed papers that mention the material with jewelry, allergy, eyewear or UV are fetched for each entry. We show what a supplier states and do not appraise or grade. CPSC recalls →