Lead Tungstate
PbWO4
Chemical name
Lead Tungstate
Mineral name
Stolzite (Lead tungstate)
Chemical formula
PbWO4
Melting point [°C]
1123
Crystal system
tetragonal
Crystal Class
tetragonal-dipyramidal (4/m)
Space Group
I4_1/a
Unit cell
a [Å]:5.50
b [Å]:5.50
c [Å]:12.12
Formula units
Z=4
Frequent crystal surfaces
{111}, {101}, {011}, {112}, {001}
Mohs hardness
2.5 - 3
Density [g/cm3]
8.28
Cleavage
cleavage plane on (101), imperfect on {001}, indistinct on {011}
Fracture / Tenacity
brittle, conchoidal to uneven
Color
reddish-brown, brown, yellowish-gray, smoky-gray, straw-yellow, lemon-yellow, may be green, orange, red
Streak
white
Transparency
translucent to transparent
Optical character
uniaxial (-)
Refractive Index
nω=2.270; nε=2.180-2.190
Birefringence δ
0.090