Found this cool rock at lake Tahoe. It has 2 white rings around it that are so perfect I thought at first they were drawn. Now it lives in my Chia pet garden. Here's an additional pic.
this post was submitted on 30 Dec 2025
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Cool Rocks
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A place for:
- Sharing cool rocks you found
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- Cool rocks
- Minerals are cool, too
Be gneiss to each other.
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Earthquake probably. The surface was that white layer then quake and now the top layer is sideways and a new layer of white is deposited. Not a geologist.
If it has a fault inside it's a very cool rock, so I'd be cautious about the possibility.
What do you mean a fault in the rock?
In geology, a "fault" is a place where rock has broken apart and the parts have moved, so the two faces don't match up any more.
This would actually be "jointing", where it's broken but there was no movement