Official iOS App & Gemology Guides

Identify, Authenticate & Appraise Fine Jewelry

Decode gold karat stamps, spot authentic Art Deco filigree, verify antique hallmarks, and research gemstone valuations with our iOS App and expert research guides.

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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.

  • Berlin Iron
  • Cast Iron Jewelry
  • Gothic Revival
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.

  • Micromosaic
  • Grand Tour
  • Millefiori
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.

  • Cut Steel
  • Marcasite
  • Pyrite
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.

  • Art Nouveau
  • Enamel Jewelry
  • Plique-a-jour
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.

  • Brooches
  • Jewelry Findings
  • Dating Antique Jewelry
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.

  • French Hallmarks
  • Gold Hallmarks
  • Eagle Head
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.

  • Silver Hallmarks
  • Sterling 925
  • British Silver
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.

  • Gold Hallmarks
  • Metal Purity
  • Jewelry Identification
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.

  • Cameos
  • Antique Jewelry
  • Carved Gemstones
Official iOS App

Download The Jewelry Appraisal iOS App

Scan hallmarks, identify gemstones, and appraise antique & fine jewelry instantly on your iPhone & iPad with AI.

Download on the App StoreFree Download • Designed for iPhone & iPad