GEOLOGY
CRYSTALLOGRAPHY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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{211}
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{101}
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{111}
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{010}
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Detailed explanation-1: -Gypsum is soft and can be scratched with a fingernail. It has four different cleavage surfaces, and its crystals display a variety of forms, the most common being a granular, massive rock known as alabaster.
Detailed explanation-2: -Gypsum comes as clear crystals that display one perfect cleavage (selenite), as blocks of featureless white rock (alabaster), and as silky fibrous blocks (satin spar).
Detailed explanation-3: -Cleavage/Fracture: Gypsum’s cleavage is complex, there is only good cleavage in one direction and fair in two others that create thin, rhombic fragments. Crystal Form: Gypsum appears mostly as a four sided crystal, otherwise known as tabular crystal. This is also identified as prismatic, acicular or bladed (8).