Fluorite is a mineral that cannot be scratched with a fingernail but will not scratch glass. Which of the following could be the hardness of fluorite? Use the scale below to answer:
Hardness of Common Objects:
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Fingernail (2.5), Piece of Copper (3.5), Iron Nail (4.5), Glass (5.5), Steel File (6.5), Streak, Plate (7), Scratches Quartz, Scratches Topaz, Scratches all common materials
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a.) 2, b.) 4, c.) 9, d.) 7
