Gemstone Knowledge
SOOKJAI KNOWLEDGE
Gemstone Knowledge
A considered guide to gemstones — from colour and cut to origin, treatment and the stories behind each stone.
Colour · Spinel
Grey Spinel: Understanding Tone, Undertone and Character
Grey spinel is far more varied than one neutral shade. Learn how light-to-dark tone, blue or violet undertones, lighting, cut and metal context shape the character of grey spinel—and why there is no single best grey.
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Spinel · Treatment
Natural Spinel: Is Spinel Usually Treated?
Natural spinel is commonly encountered without treatment, but spinel can still be heated, fracture-filled or subjected to specialised diffusion treatments. Learn what is common, what has been documented, and why untreated status should be understood rather than assumed.
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Spinel
What Is Spinel?
Spinel was mistaken for ruby for centuries, but it is a distinct gemstone with its own mineral identity, colours and market. Learn what spinel is, why it comes in so many hues, how durable it is, why treatment is relatively uncommon, and why fine spinel now stands firmly on its own.
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