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A piece of hematite may look like just a dark gray blob. That might seem difficult to identify but with a streak test you can easily identify it! Just rub the mineral against a white streak plate and
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Like real gold, pyrite is a brassy yellow color. But unlike gold, pyrite is not worth large amounts of money. That's because it is a very common mineral. It is found in all three rocks types: sedimentary,
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You can find gypsum in sedimentary rocks, deserts, and caves. Large amounts can form in layers on a salty sea or lake bottom when water evaporates leaving the mineral behind. Gypsum sometimes forms when
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What’s that on your chips? It’s a mineral called halite! If you look closely at ordinary table salt, you will see that, just like other minerals, it looks like crystals. Halite is salt. In its natural
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Calcite is typically found in the sedimentary rock called limestone. Calcite is also in marble, a metamorphic rock, which forms when limestone is put under strong heat and pressure. Calcite crystals have
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Yuck! What's that smell? When water mixes with the mineral sulfur, a chemical reaction causes a small amount of hydrogen sulfide (H2S) gas is produced. Hydrogen sulfide is the same gas that makes rotten
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You can use perfect calcite crystals to make an optical illusion called double refraction. Calcite has unique optical properties that split a ray of light into two beams that are bent at different angles
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