Ganister occurs in the hills of Alexander and Union Counties and is a
loosely consolidated, granular material consisting of irregular
particles up to about an inch in diameter or of masses of material
readily disintegrated into such particles. The particles are composed
mainly of fine crystalline quartz. Ganister is white, cream, light
yellow, or red and occurs in deposits up to 25 feet or more thick.
Relatively small tonnages of the light colored ganister are now used,
principally in making refractories, but ganister is said to have been
more widely used in that field in the past. It is produced from
underground mines. Some red ganister, or ganister like material, mined
from open pits has been used for road surfacing.