The growth and properties of large crystals of synthetic quartz

Abstract

In the last twenty years quartz has become of considerable importance to the telecommunications industry, one of its most important uses being the control of the frequency of oscillation of high-frequency transmitters. In this country alone the peak war-time demand for oscillator crystals was well over a million a year.Although quartz is very abundant in the earth's crust it is usually found in the polycrystalline state or as small crystals. Large crystals, reasonably free from twinning and flaws, are relatively rare and most of the supply for piezoelectric purposes comes from Brazil.