Cinnabar with the deadly toxin. Cinnabar Cinnabar () and cinnabarite (), likely deriving from the ("kinnabari"), refer to the common bright scarlet to brick-red form of mercury(II) sulfide (HgS) that is the most common source ore for refining elemental mercury, and is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments. Cinnabar generally occurs as a vein-filling mineral associated with recent volcanic activity and alkaline hot springs. The mineral resembles quartz in symmetry and in its exhibiting birefringence; cinnabar has a mean refractive index of approximately 3.2, a hardness between 2.0 and 2.5,
USS Cinnabar (IX-163) USS Cinnabar (IX-163) USS "Cinnabar" (IX-163), a designated an unclassified miscellaneous vessel, was the only ship of the United States Navy to be named for cinnabar. Her keel was laid down in 1944. She was acquired on a loan-charter basis from the War Shipping Administration and placed in service at San Francisco, California, on 26 September 1944. She was assigned to the Pacific Fleet, and in November 1944 departed the West Coast in tow for Pearl Harbor. With Service Squadron 8, and later Service Squadron 10, she issued general stores to advanced bases at Eniwetok, Espiritu Santo, Ulithi, Leyte, and