- Mount Diablo Mine (Mt. Diablo Mine; Ryne Mine), Mount Diablo, Clayton, Contra Costa Co., California, USA
- Small Cabinet, 6.5 x 4.5 x 3.0 cm
- Ex. John Ydren
Metacinnabar is an uncommon mercury ore worldwide. Lustrous, complexly rounded, dark gray metacinnabar crystals to 5 mm richly cover the quartz-rich matrix plate from the Mt. Diablo Mine of California. Ex John Ydren Collection. Older material.