FREE KNOWLEDGE · PRACTICAL GEMOLOGY

The Self-Guided Revival Gem Lab

Learn how to observe, test and compare gemstones at home or at a workbench. Each station explains the tool, method, useful clues, quality indicators and limits. No submission and no fee—this knowledge is here to be shared.

What We Research

From an unreadable hallmark to a piece with an unknown history, we examine the details that can reveal what your jewelry may be.

01 — Daylight & 10× Loupe

Use neutral daylight, a white card, tweezers and a 10× loupe. Check color zoning, cut symmetry, polish, chips, bubbles and inclusions from several angles. These clues guide the next test; they do not prove identity.

02 — UV Fluorescence

Using a dark viewing area, eye protection and 365 nm long-wave UV, observe the reaction and any afterglow. Compare a known reference beside the unknown. UV alone never confirms quality or origin, and you should never look directly into the lamp.

03 — Refractive Index & Optics

Use a refractometer, approved contact liquid, polariscope and dichroscope. Take several readings on a clean polished facet and compare the range and birefringence with a trusted chart.

04 — Specific Gravity

With a 0.01 g scale, water cup and fine suspension thread, record dry weight and suspended weight. Specific gravity = dry weight ÷ (dry weight − suspended weight). Test loose, clean stones only.

05 — Thermal & Electrical Tests

Use a calibrated diamond/moissanite tester on a clean, dry stone at room temperature. A tester separates some common simulants but does not grade cut, color, clarity or natural versus laboratory origin.

06 — Hardness, Streak & Scratch

Scratch testing can permanently damage a gemstone and should not be your first test. Use established references and non-destructive observations whenever possible; seek professional testing when identity or value matters.

Know the Limits

At-home observations are clues, not a laboratory report or appraisal. Valuable, mounted, fragile or uncertain stones should be examined by a qualified gemologist using appropriate instruments.