closed as off-topic by Jan Doggen, uhoh, Fred, Semidiurnal Simon, BillDOe Aug 27 at 21:17
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "Questions about rock identification requests are off-topic. For more information, see the announcement on meta." – Jan Doggen, uhoh, Fred, Semidiurnal Simon, BillDOe
That’s labradorite, it’s a silicate and a type of plagioclase feldspar named after Labrador, Canada. The iridescent colours that are seen is called the “schiller” effect. It is caused by light being scattered by thin layers of feldspar within the rock that formed as it cooled.