5.56 ct Gray Opal - Trillion

At 5.56 carats, this opal from Ethiopia carries its gray color through a trillion cut, measuring 14.5 x 12.4 x 6 mm.

Opal is hydrated silica that can break white light into a play of living color, a fire no two stones repeat; it holds up to a fifth of its weight in water, which is why it glows in a way nothing crystalline does. It is entirely untreated; no heat, no enhancement, the color exactly as the earth made it.

Its exact combination of color, cut, and origin is its own, the kind of center stone you choose on purpose and build a piece around. Hand-selected and filmed by Caveman Gems in good light, shown as honestly as a screen allows.