How do the properties of a rock change when it becomes a metamorphic rocks?

Answer 1

The parent rock is exposed to varying degrees of pressure and/or heat either from depth of burial, exposure to a plutonic body of intense heat, or from pressures resulting from the collision of tectonic plates. The heat and/or pressure can transform the minerals inside the parent rock to new minerals, cause recrystallization of existing minerals, or reorganize the existing minerals into bands and layers. Exchanges of elements can also occur from hot fluids associated with plutonic intrusions. All of these processes take place without any melting of the parent rock.

Answer 2

It changes its appearence, texture, crystal structure, and mineral content change. This is the answer according to the Georgia Earth Science book.

Answer 3

The crystals in the rock either get larger or smaller, depending on where it formed. A rock's texture is determined by the size and shape of the crystals inside the rock.