Its piezoelectric (pee-AY-zo-"electric") properties make it allows its use in crystal oscillators.
At very high pressure, such as below impact craters, this mineral can metamorphose into coesite (KO-uh-zite). Evidence of the K-T boundary was provided by a layer of the amorphous "shocked" type of this mineral. Together with various types of feldspar, this mineral comprises the major ingredient of granite. Its piezoelectric (pee-AY-zo-"electric") properties make it allows its use in crystal oscillators. For 10 points, name this mineral made up of silicon dioxide, which has a hardness of seven on the Mohs scale.
At very high pressure, such as below impact craters, this mineral can metamorphose into coesite (KO-uh-zite).
{quartz} [before "{silicon}," accept {silicon dioxide}; or {silica}; or {SiO2}]