Gemstone Encyclopedia

White Sapphire: What the Name Means and Why Deposit Type Matters

White Sapphire: What the Name Means and Why Dep...

White sapphire is a trade name for near-colorless corundum. Learn what the name means, how primary and secondary deposits form, and why deposit type does not equal quality.

White Sapphire: What the Name Means and Why Dep...

White sapphire is a trade name for near-colorless corundum. Learn what the name means, how primary and secondary deposits form, and why deposit type does not equal quality.

Coral as a Gem Material: Why It Is Neither Mineral nor Fossil

Coral as a Gem Material: Why It Is Neither Mine...

Precious coral is a biogenic organic gem material, not a mineral species or fossil. Understand its calcium carbonate structure, organic pigment color, properties, occurrence, and identification limits.

Coral as a Gem Material: Why It Is Neither Mine...

Precious coral is a biogenic organic gem material, not a mineral species or fossil. Understand its calcium carbonate structure, organic pigment color, properties, occurrence, and identification limits.

Rhodochrosite’s Pink Glow: Born of Manganese, Not Interference

Rhodochrosite’s Pink Glow: Born of Manganese, N...

Rhodochrosite’s rose-pink color comes from manganese in the carbonate structure, not iridescence. Distinguish body color from banding, chatoyancy, and surface effects.

Rhodochrosite’s Pink Glow: Born of Manganese, N...

Rhodochrosite’s rose-pink color comes from manganese in the carbonate structure, not iridescence. Distinguish body color from banding, chatoyancy, and surface effects.

Pigeon Blood Ruby: Why the Trade Name Is Not a Mineral Identity

Pigeon Blood Ruby: Why the Trade Name Is Not a ...

Pigeon blood ruby is a trade color term, not a mineral species. Learn how ruby classification works, why chromium colors corundum red, and how natural and synthetic ruby are distinguished.

Pigeon Blood Ruby: Why the Trade Name Is Not a ...

Pigeon blood ruby is a trade color term, not a mineral species. Learn how ruby classification works, why chromium colors corundum red, and how natural and synthetic ruby are distinguished.

Why Rhodochrosite Ranges from Rose to Raspberry: Trace Chemistry and Color Variation

Why Rhodochrosite Ranges from Rose to Raspberry...

Rhodochrosite ranges from pale pink to raspberry red because manganese occupancy and substitution by other cations control its color. Learn the mineralogical reasons for this variation.

Why Rhodochrosite Ranges from Rose to Raspberry...

Rhodochrosite ranges from pale pink to raspberry red because manganese occupancy and substitution by other cations control its color. Learn the mineralogical reasons for this variation.

Why Bloodstone's Green and Red Spots Cannot Reveal Where It Came From

Why Bloodstone's Green and Red Spots Cannot Rev...

Bloodstone appearance does not reliably indicate geographic origin. Learn how chalcedony forms, why red iron-oxide spots vary, and why source attribution needs more than visual inspection.

Why Bloodstone's Green and Red Spots Cannot Rev...

Bloodstone appearance does not reliably indicate geographic origin. Learn how chalcedony forms, why red iron-oxide spots vary, and why source attribution needs more than visual inspection.