Mineral Factbook

Metacinnabar

HgSIMA symbol: Mcingrandfathered

Metacinnabar is a sulfide or sulfosalt mineral with the formula HgS, crystallizing in the cubic system. It has a Mohs hardness of 3, typically black or gray in color, with a metallic luster, a specific gravity of 7.81. Its streak is black.

Photos

Metacinnabar specimen photo
Nessa Eull · CC0 · Commons
Metacinnabar specimen photo
Robert M. Lavinsky · CC BY-SA 3.0 · Commons
Metacinnabar specimen photo
Robert M. Lavinsky · CC BY-SA 3.0 · Commons
Metacinnabar specimen photo
Robert M. Lavinsky · CC BY-SA 3.0 · Commons

Crystallography

Crystal systemcubic crystal systemWikidata (CC0)
Space groupF -4 3 m
Cell (Å, °)a = 5.8517, b = 5.8517, c = 5.8517; α = 90, β = 90, γ = 90
Cell volume200.376 ų, Z = 4
Axial ratios1.0000:1:1.0000calculated from COD 9008848
Source structureCOD 9008848 (Crystal Structures, 1963) — 1 of 2 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)3.3782.0691.7642.9261.3421.194
I/I₀10051.748.634.92018.1

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9008848; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)7.712 g/cm³calculated from COD 9008848
Hardness (Mohs)
3single sourceDana, System of Mineralogy, 6th ed. (1892)
Specific gravity
7.81 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892)
Color
black, graysingle sourceDana, System of Mineralogy, 6th ed. (1892)
Streak
blacksingle sourceWikidata (CC0)
blacksingle sourceDana, System of Mineralogy, 6th ed. (1892)
Luster
metallicsingle sourceDana, System of Mineralogy, 6th ed. (1892)

Chemistry (calculated)

Molecular weight232.66 g/molcalculated from the IMA formula
Composition (wt%)Hg 86.22%, S 13.78%

Classification

Nickel-Strunz (10th)2.CB.05aWikidata (CC0)
Nickel-Strunz (9th)2.CB.05aWikidata (CC0)