Labradorite

Labradorite is a feldspar, and the flash of blue and green across its surface has a name: labradorescence. It comes from light bouncing between microscopic layers inside the stone, so the colour shifts as you move: deep blue at one angle, green at another, and darker where the light does not reach.

It was identified in the 1770s on the coast of Labrador in Canada, which is where the name comes from.

Traditionally associated with protection and transformation.