Cinnabar
Cinnabar, or cinnabarite, also known as mercurblende is the bright scarlet to brick-red form of mercury(II) sulfide. It is the most common source ore for refining elemental mercury and is the historic source for the brilliant red or scarlet... Wikipedia
Mineral chemical formula: HgS
Cleavage: Prismatic, perfect
Color: Cochineal-red, towards brownish red and lead-gray
Crystal system: Trigonal
Fracture: Uneven to subconchoidal
Luster: Adamantine to dull
Mohs scale hardness: 2.0–2.5