Stone Identification – Behavior

Stone Identification – Behavior

When we talk about mineral behavior, it’s not like you can give a rock a Time Out for acting up. Behaviors, in terms of stones, refer to the natural form of its crystal and what happens if you break it. Crystal Behavior This one only matters if you’re dealing with obvious crystals, vs. a stone that’s just a rough rock. Different specific minerals grow into crystals that have identifiable shapes and other clues to their species. For example, Fluorite crystals tend to terminate in pyramid-shaped points: four sides, more or…

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Stone Identification – Streak

Stone Identification – Streak

If you’re a child of the *mumbles a decade* you’ll remember a Ray Stevens song called The Streak. This is not about that song, but if you want to hum along as you read, be my guest. You find a stone’s streak by scraping it over a streak stone, generally unglazed porcelain tile in either black or white. If you don’t have an official streak plate and have an old porcelain bowl or plate, you can use the bottom of that as long as it’s not glazed. Minerals are just…

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Stone Identification – Hardness

Stone Identification – Hardness

Moh’s Scale Possibly one of the most common ways to sort out what kind of stone you’ve found is a hardness test. When you can pinpoint how hard your mineral is, you can start to narrow down its family considerably. The standardized scale for mineral hardness is the Moh’s Scale, which starts at a 1 for talc (which can be scratched with a fingernail) and terminates at a 10, the diamond, which is the hardest naturally-occurring mineral. Notice I said naturally-occuring minerals. There have been harder products manufactured in the…

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Stone Identification – Light

Stone Identification – Light

Stone Appearance – Luster Believe it or not, color isn’t the first thing to look at when you’re trying to identify a rock or mineral. One of the first things to consider is its luster – the way it reacts to light. Keep in mind, I’m not talking about polished stones, which can be misleading, but what you’ll see in a raw piece of stone broken off from the matrix (or parent stone.) Look closely at the part that sheared away, because it can give you a lot of cues….

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What Kind of Rock Do I Have?

What Kind of Rock Do I Have?

Our Facebook group has brought a few people together and one of the questions that keeps coming up is, “How do I identify what I’ve found?” If only it was as simple as a color test: “If it’s blue, it’s turquoise; if it’s yellow, it’s citrine.” Of course it isn’t that simple, though visual cues can certainly play into the mix. For example, turquoise generally runs in shades of, well, turquoise, though it can lean more to the green on occasion. Rose quartz will always be pink, and true amethyst…

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