Metamorphic
meta·mor·phic | ˌme-tə-ˈmȯr-fik
adjective
A rock that has been affected by pressure, heat, and water, resulting in a more compact and highly crystalline condition
Metamorphic rock starts as another form of rock but undergoes significant changes due to the application of heat, pressure, fluids, or other combination of influences. Deep in the Earth’s crust, due to the movement of the plates and the extreme conditions, this happens frequently. Many gemstones are found in metamorphic rock, including beryls that include emerald, aquamarine, and morganite. Additionally, metamorphic rocks may consist of sapphires, rubies, zircon, and spinel. The continued application of these conditions can also transform an already transformed rock into something different entirely.