My uncle swore by using a vinegar soak for cleaning calcite off a fossil I dug up near Cincinnati, and after a week of watching it fizz, the detail was incredible.

Kelly Henderson · 2026-03-23T08:40:04.853207+00:00

Has anyone else had luck with mild acids on different minerals, or is it a quick way to ruin a good find?

Honestly I was always scared to try it, but seeing the results on some limestone last year totally won me over. Just gotta be so careful with the timing.

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derekcarr4mo ago

...and that's exactly how I ended up with a pile of gravel that used to be a trilobite. My uncle told me the same thing about vinegar, swore by it for years. I tried it on a piece of limestone with some small brachiopods and it came out great, like the rock just melted away. Then I got cocky and tried it on a darker calcite chunk and it just crumbled into a sandy mess. Lesson learned: know your mineral better than I know myself apparently.

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emeryw166mo ago

Yeah I was the same as @jennyh33, but vinegar on some pyrite from Illinois proved me wrong. Just don't walk away from it.

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