Price Guides
+2
Nov 6, 2026
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2 min read
What large tanzanite has sold for, and what GIA says drives its value.
Tourmaline
What Paraíba tourmaline has sold for, and why a price per carat can mislead.
4 min read
What sapphires sell for by size, treatment and origin, with a named source for every figure.
Nov 3, 2026
What a ruby is actually worth by quality, origin, treatment and size, and how to read the numbers.
