Keystone Quarry

Keystone Quarry

Industrial facilities-Washington-Stevens; Mining-Washington-Chewelah; Quarrying-Washington-Stevens;

1965.30.033; Keystone Quarry; Originally the United States Marble Co. This quarry opened in 1903, produced black marble which graduated to various shades of green. The material at this time intended for building use was actually brucite or magnesium hydrate but was not recognized as important until 1915. World war I accelerated the need for magnesite and foreign supply (largely Austria) was decreased. In 1916, the Keystone was shipping magnesite but in 1917, the Finch deposit was opened and the Keystone abandoned. In 1942, the Keystone was again opened and all marketable ore was finally removed by 1966.

Chewelah Museum

http://crossroadsarchive.org/rights/chewelah-museum

Still image

http://crossroadsarchive.net/upload/scpa00100119088.JPG