Topic
Grading
Grading entries on Zultpedia cover how color-change diaspore is evaluated for color, clarity, cut, and carat weight, including the importance of color-change strength (the percentage shift between daylight and candlelight illuminants) as the dominant value driver across all per-carat price bands.
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Property Guide
Toughness of Zultanite — Why Hardness Alone Lies
Zultanite's 6.5–7 Mohs hardness measures scratch resistance, not toughness. Toughness — resistance to chipping and cleaving under impact — is rated only "fair" for diaspore because of its perfect {010} cleavage. A…
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Education Article
How to Read a GIA Zultanite Report
A GIA color-change diaspore report documents seven facts you must verify: species (must read "diaspore"), variety (must read "color-change"), weight to two decimals, dimensions, cut style, refractive index range (1.682–1.752 expected), specific…
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Education Article
How to Insure Zultanite Jewelry
Insure Zultanite jewelry through a specialty jewelry-insurance carrier (Jewelers Mutual, Chubb, BriteCo) rather than relying on a homeowner's policy, which typically caps gem coverage at $1,000–$2,500. Insure for replacement value at current…
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Gem Article
The Durability of Zultanite Jewelry — Hardness Versus Toughness
Zultanite's 6.5–7 Mohs hardness puts it in the "scratchable by quartz dust" range, suitable for occasional-wear jewelry but not daily-wear rings. More importantly, the perfect cleavage on the {010} plane gives diaspore…
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FAQ Cluster
Zultanite Price and Value — Frequently Asked Questions
Zultanite has a suggested-retail price table from Zultanite Gems LLC ranging from USD 750 per carat for stones under one carat to USD 14,000+ per carat for stones above 20 carats. Per-carat…
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Education Article
Buying Zultanite Without Getting Cheated — A Buyer’s Checklist
Five buyer protections for Zultanite: (1) demand a gemological lab report from GIA, IGS, or a recognized national lab confirming species and origin, (2) verify color change in person under multiple illuminants,…
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Education Article
Caring for Zultanite Jewelry — Cleaning, Storage, and Wear
Zultanite jewelry needs three protections: (1) clean only with warm soapy water and a soft brush — never ultrasonic or steam, which can propagate cleavage, (2) store separately from harder gems (sapphire,…
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Property Guide
Hardness of Zultanite — 6.5 to 7 on the Mohs Scale
Zultanite (gem-quality color-change diaspore) measures 6.5 to 7 on the Mohs hardness scale, comparable to peridot and below quartz. This places it in the moderately hard range — durable enough for pendants,…
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FAQ Cluster
Zultanite — Frequently Asked Questions
Frequently asked questions about Zultanite — gem-quality color-change diaspore from the İlbir Mountains of Türkiye. Twenty Q&A pairs covering identity, rarity, sourcing, color, jewelry use, and buying guidance. Sourced from peer-reviewed mineralogy,…
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Gem Comparison
Zultanite vs Alexandrite — Two Gems, One Phenomenon, Different Propositions
Zultanite (color-change diaspore) and alexandrite (color-change chrysoberyl) are mineralogically unrelated species that produce a similar visual phenomenon — the alexandrite effect — through different chemistries. Alexandrite is harder (8.5 vs 6.5–7 Mohs),…