Essential Question:

Cleavage When a mineral is split into pieces and produces regular planes that reflect light. Fracture When a mineral breaks into pieces with jagged, rough edges. Color Sometimes can help you, can sometimes fool you. Streak Produced by scraping a mineral sample across an unglazed, white tile. Not always the same color as the mineral itself. Luster How light reflects from a mineral’s surface. Hardness What scratches the mineral and what can be scratched by it. Moh’s Scale A way to classify minerals by hardness on a scale from 1 to 10. One is the softest, ten is the hardest. Specific gravity How heavy it feels, heft. Other Properties These include attracting a magnet, reacting to acid, double refraction, and taste.

Cleavage When a mineral is split into __________ and produces __________ planes that reflect light. Fracture When a mineral breaks into pieces with __________, rough edges. Color Sometimes it can __________ you, can sometimes __________ you. Streak Produced by __________ a mineral sample across an unglazed, white______. Not always the same ________ as the mineral itself. Luster How __________ reflects from a mineral’s surface. Hardness What _____ the mineral and what can be __________ by it. Moh’s Scale A way to classify minerals by __________ on a scale from 1 to 10. One is the __________, ten is the hardest. Specific gravity How __________ it feels, heft. Other Properties These include attracting a __________, reacting to acid, double refraction, and _____.

How the Mohs Scale works: On each level of the scale a mineral can be scratched by something of the same or higher level, but nothing lower. Test your mineral specimen by trying to scratch it with your fingernail. If it can be scratched by your fingernail, it has a hardness of If it doesn't scratch, next try a copper penny. If you are able to scratch your specimen with the penny but not with your fingernail, it has a hardness between 2.5 and 3.5. If the specimen does not scratch with a penny, try the nail. If it cannot be scratched with the penny, but can be scratched with the nail, it has a hardness of A diamond can only be scratched by another diamond.