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Found a weird green layer in a creek bed near my house
I walk my dog along this same creek in Springfield almost every day. About two months ago, after a big storm, I noticed a patch of bright green rock showing through the usual brown mud. It looked like someone spilled paint. I took a small piece home and checked it with my basic field guide. Turns out it's malachite, which forms when copper minerals get wet and react with air. The crazy part is that I went back last weekend and the green patch is now about three feet long and way more obvious. The water flow must be slowly washing away the mud covering it. I've never seen a mineral deposit just appear like that over a few weeks. Has anyone else watched a rock formation change right in front of them?
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jason_wood1mo ago
That's wild about the malachite just showing up. I saw something like that once where a new spring popped up and left this weird orange rust stain all over the rocks.
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williams901mo ago
That orange rust is probably iron bacteria, not just regular oxidation. It forms that slimy film when groundwater with dissolved iron hits air. Kind of gross but totally natural.
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lisa_hart261mo ago
Actually disagree, that green layer sounds more like algae to me. Malachite doesn't just spread that fast in a creek.
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