Nagyágite

[Pb₃(Pb,Sb)₃S₆](Au,Te)₃IMA symbol: Ngygrandfathered

Nagyágite is a sulfide or sulfosalt mineral with the formula [Pb3(Pb,Sb)3S6](Au,Te)3, crystallizing in the monoclinic system. It has a Mohs hardness of 1-1.5, typically black or gray in color, with a metallic luster, a specific gravity of 6.85-7.2. Its streak is black or gray.

Photos

Crystallography

Crystal system	monoclinic crystal systemWikidata (CC0)
Space group	P 1 21/m 1
Cell (Å, °)	a = 4.22, b = 4.176, c = 15.119; α = 90, β = 95.42, γ = 90
Cell volume	265.247 Å³, Z = 2
Axial ratios	1.0105:1:3.6205calculated from COD 9002154
Source structure	COD 9002154 (American Mineralogist, 1999)

Powder X-ray diffraction (calculated)

d (Å)	3.01	2.87	3.651	3.825	2.821	2.406
I/I₀	100	87.6	59.9	56.4	53.2	47.8

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9002154; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)	7.144 g/cm³calculated from COD 9002154
Hardness (Mohs)	1-1.5single sourceDana, System of Mineralogy, 6th ed. (1892)
Specific gravity	6.85-7.2 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892)
Color	black, graysingle sourceDana, System of Mineralogy, 6th ed. (1892)
Streak	black, graysingle sourceDana, System of Mineralogy, 6th ed. (1892)
Luster	metallicsingle sourceDana, System of Mineralogy, 6th ed. (1892)

Classification

Nickel-Strunz (10th)	2.HB.20aWikidata (CC0)
Nickel-Strunz (9th)	2.HB.20aWikidata (CC0)