I visited the Science Campus of the Helsinki University as there was a Geology Day. In the yard there is a large block of igneous rock mainly consisting of special feldspar mineral called spectrolite. In a polished surface it shows all the spectral colours when viewed in a certain direction.

Spectrolite is a Finnish version of a more general mineral labradorite found else were in the world.

The last image shows both the raw and the polished surfaces.

[daacon]

Cool images Georg - that must have been neat to see in person.

[cupic]

Its glowing thanks for sharing


cheers

[heliphoto]

Amazing. Reminds me of the last time I broke a LCD.

[gawan]

Thanks for the comments! Now I have to work out some artistic photos out of these! Here I was simply amazed about the phenomena!