11.21 ct Gray Opal - Oval

At 11.21 carats, this opal from Ethiopia carries its gray color through an oval cut, measuring 22 x 14 x 7.5 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 wholly untreated, its color finished by geology rather than by any furnace or enhancement.

A single natural gemstone with no duplicate behind it; once it is set or collected, there is no other. It will outlast everyone who owns it, which is most of what an heirloom really is. Hand-selected and photographed by Caveman Gems in good light, shown as honestly as a screen allows.