Birthstones · Month 10 of 12

October Birthstone: Opal

October’s stones are opal and tourmaline. The Collection holds both.

Opal is silica spheres in a lattice, and it holds water. The rolling colour is diffraction off those spheres, so no two opals play alike.

The Optics

Opal's play-of-colour comes from light diffracting through orderly stacked spheres of silica.

What’s Your Gem?

One-time payment. All 15 stones on any device, yours permanently. Stones still being cut arrive here at no extra cost. The Quiz is free and asks for nothing.

See the stone on its own: Opal. October’s second stone is Pink Tourmaline.

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