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Hand sample identification beats staring at a screen any day
I spent two days trying to figure out a weird green mineral from a sample near Butte, Montana using online databases and thin section photos. Then I just took it to the lab and scratched it with a steel nail. It was epidote, and the hardness test told me in 10 seconds what the computer couldn't. When did we stop trusting basic field tools? What's the last rock you figured out with a simple physical test?
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harperg761mo ago
Nah, screens have their place too.
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Scratch that green stuff with a pocket knife first. If the blade leaves a mark, you're probably looking at chlorite or talc. If it doesn't, then move to the steel nail for epidote. That hardness step test saves so much time.
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parker1831mo ago
Yeah, the hardness step test is a total game changer. I used to just guess or try to scratch everything with whatever was in my pocket. Starting with the knife blade like you said stops you from wasting effort on the softer minerals. I've definitely ruined a few nail tips trying to scratch talc before I learned that order. It makes the whole process feel less like random poking and more like actual detective work.
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