How do quartz deposits form?

Question

How do quartz deposits form?

Answer 1

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Answer 2

Quartz is one type of sedimentary rock.Sedimentary rocks form in the following way.

Ignesious rocks(molten rock or magma which migrates up to the crust) exposed at the surface undergo weathering and erosion,which produces sediment.This is eventually carried out to sea,where it collects in layers.These become incresingly deeply buried and compressed by the weight of the overlying layers to form sedimentary rock.