METAMORPHIC ROCKS
Metamorphic
Rocks are formed by the alteration of pre-existing
rocks through the action of heat, pressure, and or
chemical action. The original rock might have
been igneous, sedimentary, or even metamorphic.
The changes include the formation of new minerals
out of old ones as well as the rearrangement of
existing minerals. Metamorphic rocks grade
from only slightly altered to highly
"metamorphosed." The new minerals formed
provide a clue as to the intensity of metamorphism.
(Copied from
the box the rocks came in...)
