Answer: Refers to the general temperature & pressure conditions that prevailed during metamorphisms. As the pressure & temperature increase, rocks undergo metamorphism at higher metamorphic grade.
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Answer:
Explanation: Streak plate is used to test minerals because the residue that is left on the streak plate after rubbing a mineral can be used to identify the types of minerals color. However, streak plate is small porcelain that cannot be coated with any type of glaze.