The Dallas Gem mine goes under various titles, so may also be called the California State Gem mine; Benitoite mine; Benitoite Gem mine or simply Gem mine. It is a fascinating locality high in the Diablo Range of San Benito County, California and although only 31 mineral species are recorded (a reasonably respectful number mind you), it is the type locality to six of these, a remarkably high 19% of the minerals occurring there, one of which is Benitoite-(Mn). The inky sky blue triangular crystals of Benitoite and elongated, lustrous black Neptunite crystals cover a matrix of snow white Natrolite. The is a very rich 360 degree specimen which displays well from any direction.