Hallmarks & Metal Purity
White Gold vs Yellow Gold: Same Karat, Different Alloy
White and yellow gold of one karat hold the same gold and carry the same stamp. What differs: the alloy metals, rhodium plating, hardness, solder and nickel.
Jewelry Identification & Appraisal Directory
Expert research articles and reference guides to assist jewelers, collectors, and enthusiasts in identifying, dating, and valuing fine jewelry.
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Carved Gems & Cameos
Antique Shell Cameo Identification: Which Shell Is It?
Identify an antique shell cameo: confirm it is shell, read the ground colour to name the helmet or conch it came from, and what that can and cannot date.
Carved Gems & Cameos
White Gold Cameo Jewelry Sets: How Old Is Yours Really?
Date a white gold cameo set: what the mount metal rules in or out, the stamps to read, the earring backs, and how to tell a true parure from an assembled set.
Hallmarks & Metal Purity
White Gold Wedding Bands: Stamps, Rhodium and Yellowing
Identify a white gold wedding band: read the 14K/585 and 18K/750 stamps, see why rhodium wears through to yellow, and tell it from platinum and tungsten.
Hallmarks & Metal Purity
Sterling Silver Ring Identification: Stamps, Marks & Tests
Identify a sterling silver ring: read the marks inside the band (925, STERLING, lion passant), spot plated fakes, and learn why some rings carry no mark at all.
Carved Gems & Cameos
Gold Cameo Ring Identification: Gold, Shell or Stone?
Identify a gold-toned cameo ring: read the shank stamp (14K, 9ct, 1/20 12K GF, RGP, HGE), then tell a shell, hardstone, glass or resin cameo apart.
Hallmarks & Metal Purity
Silver Prices Explained: What Your Sterling Silver Is Worth
Turn a dealer's silver price into the value of sterling: spot, bid and ask, the melt formula, a factor for 925, 900 and 800 silver, and what buyers really pay.
Hallmarks & Metal Purity
14K Yellow Gold: What Is in the Alloy and Why It Looks Paler
What 14k yellow gold is made of: 58.3% gold plus silver, copper and zinc, why it looks paler than 18k, and why color alone never tells you the karat.
Hallmarks & Metal Purity
How to Identify the Carat of Gold: Stamps, Acid and Density
Find the karat (carat) of gold: read the stamp first, then test unmarked pieces with touchstone and acid, specific gravity or XRF, and know what each one misses.
Hallmarks & Metal Purity
24K Gold Bar Identification: Stamps, Serials and Fakes
Read a 24k gold bar's stamps: refiner, 999.9 fineness, weight, serial and year. Tell cast from minted bars, check the assay card, and spot tungsten fakes.
Carved Gems & Cameos
Vintage Cameo Brooch Identification: Dating the Face
Date a vintage cameo brooch from the carved face: nose shape, hairstyle, habillé jewels, which way it faces, and how to tell a real sitter from an ideal head.
Hallmarks & Metal Purity
How Much Is 14K Gold Worth? Melt Value by the Gram
Work out what 14k gold is worth from its weight and today's gold price: the melt value formula, a factor for every karat, and why a buyer pays less than melt.
Hallmarks & Metal Purity
What Does 950 Mean on Jewelry? Platinum, Silver or Two-Tone
A 950 stamp means 95% pure metal, but which metal? Tell Pt950 platinum from 950 silver, see why 950 gold is a myth, and read 950/750 on a two-tone ring.
Dating & Construction
Berlin Iron Jewelry: Identification & Dating Guide
Identify Berlin iron: lacquered sand-cast openwork, wirework chain, the neoclassical-to-Gothic shift, and the magnet test that separates it from jet.
Mosaics & Grand Tour
Roman Micromosaic Jewelry Identification & Dating Guide
Tell a Roman micromosaic from millefiori souvenir ware, pietra dura and painted copies: tesserae shape and count, the ground, the mount, and the back.
Dating & Construction
Cut Steel vs. Marcasite: Identification & Dating Guide
Tell antique cut steel from marcasite: grey riveted studs against brassy grain-set pyrite, the magnet test, facet counts, and what the reverse reveals.
Dating & Construction
Art Nouveau Jewelry Identification Guide: Enamel & Motifs
Identify authentic Art Nouveau jewelry (1890–1910) using plique-à-jour enamel, whiplash curves, insect motifs, and maker marks from Lalique & Marcus & Co.
Dating & Construction
Antique Brooch Clasp Dating Guide: Pin, Hinge & Catch
Date an antique brooch from its findings: tube and round hinges, C-catch, trombone and safety catches, with the patent years and the attribution windows.
Hallmarks & Metal Purity
French Gold Hallmarks & Eagle Head Identification Guide
Learn how to decode French gold hallmarks: Tête d'Aigle (Eagle's Head), Boar's Head silver, Dog's Head platinum, and assay stamps from 1838 to today.
Hallmarks & Metal Purity
Platinum 950 vs. White Gold Identification & Valuation Guide
Learn how to distinguish Platinum 950 (Pt950) from 14K/18K White Gold by weight density, hallmark stamps, patina, rhodium plating, and non-destructive testing.
Carved Gems & Cameos
Victorian Mourning Jewelry & Whitby Jet Identification Guide
Learn how to identify authentic Whitby Jet, Vulcanite (hard rubber), French Jet (black glass), and Gutta-Percha in Victorian mourning brooches and rings.
Hallmarks & Metal Purity
British Sterling Silver 925 Hallmarks Identification Guide
Learn how to decode British sterling silver hallmarks: the Lion Passant, town marks (London, Birmingham, Sheffield), and date letters from 1700 on.
Hallmarks & Metal Purity
Gold Purity Stamps & Karat Hallmarks Identification Guide
Comprehensive guide to decoding gold hallmarks, karat stamps (10k, 14k, 18k, 24k, 585, 750), maker's marks, and testing techniques for antique and fine jewelry.
Vintage Rings
Art Deco Engagement Ring Authentication & Identification Guide
Learn how to identify authentic 1920s-1930s Art Deco engagement rings, spot geometric filigree, old European cut diamonds, platinum marks, and reproductions.
Carved Gems & Cameos
Antique Cameo Jewelry Identification & Value Guide
Learn how to identify genuine shell, hardstone, coral, and glass cameos, evaluate carved portrait details, date hardware clasps, and spot molded plastic fakes.
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