Rare specimen Cerussite Nakhlak Mine, Anarak District, Esfahan Province
very rare specimen
95 mm x 56 mm x47 mm
weight 2511 carats
Cerussite is an interesting mineral, forming in an array of fascinating crystal formations and bizarre twinning habits. It is easily identifiable by its heavy weight, brilliant luster, and crystal habits. Cerussite also performs interesting reactions during blowpipe testing. Specimens may be fragile and should be handled with care.
Chemical Formula PbCO3
Composition Lead carbonate, sometimes with silver and chromium
Variable Formula (Pb,Ag,Cr)CO3
Color Colorless, white, cream, light gray, light yellow, and brown. May also be lightly tinted blue, green, or red.
Hardness 3 - 3.5
Crystal System Orthorhombic
3D Crystal Atlas
(Click for animated model)
Complex Wide Crystal
Repeated Penetration Sixling
Highly Elongated Tabular
and Aggregates Cerussite forms some of the most interesting, complex, and varied crystals and groupings in the mineral kingdom. Its most prevalent form is as small, flat, thin plates, as well as prismatic and tabular crystals. Crystals frequently twin to form interesting shapes, such as star, heart, sixlings, and v-shaped twins. A highly coveted form is reticulated growths of thin crystals which form a delicate, snowflake-like mass. Also reticulated, acicular, radiating, coxcomb, in wheat sheaf form, fibrous, and massive. Crystal faces are usually striated.
Transparency Transparent to translucent
Specific Gravity 6.5 - 6.6
Luster Greasy to adamantine. Fibrous growths, which are rare, may be silky.
Cleavage 1,1 - prismatic
Other ID Marks Commonly fluorescent, usually cream-white to yellow in shortwave ultraviolet light
Complex Tests Weakly effervesces in hydrochloric acid, and dissolves in nitric acid
In Group Carbonates; Aragonite group
Striking Features Luster and heaviness associated with the light color
Environment Forms as a secondary mineral from oxidized lead deposits, especially in arid regions.
Rock Type Sedimentary, Metamorphic
Popularity (1-4) 2
Prevalence (1-3) 3
Demand (1-3) 1