And this history from 1973 states that synthetic crystals for civilian use were not grown until about 1958: www.tedlind.net/Dickinson%20Paper.htm
"The government started the development of artificial quartz through a RD (Research & Development) contract to Fort Monmouth. About the same time P. R. Hoffman began to develop the first civilian source in 1958 under the direction of his chief chemist, Warren J. Hunt.(63) During the sixties the synthetic quartz process was steadily improved, until most companies today use at least 50% synthetic quartz in their products."