Labradorite
A dark pebble? Catch the light and it flashes from deep inside with iridescent veins of peacock blue, greens, golds and rusts.
When labradorite cooled from a melt, silicate minerals, albite and anorthite, that were miscible at high temperatures became incompatible and separated into two phases. The phases are arranged in stacked alternate layers and it is these that produce the iridescent colours by multi-layer interference.
The colours of a coated camera lens are produced in the same way.
More about labradorescence...
Labradorite
A dark pebble? Catch the light and it flashes from deep inside with iridescent veins of peacock blue, greens, golds and rusts.
When labradorite cooled from a melt, silicate minerals, albite and anorthite, that were miscible at high temperatures became incompatible and separated into two phases. The phases are arranged in stacked alternate layers and it is these that produce the iridescent colours by multi-layer interference.
The colours of a coated camera lens are produced in the same way.
More about labradorescence...