Crystal system:             Orthorhombic                            Hardness:         3 - 3,5
 
Density:                        6,5 average                               Cleavage:         good
 
Streak:                          white                                          Colour:              colourless. white, gray, blue, and green
Colour:
Occurrence:                  Occurrence: It is a lead carbonate mineral, usually found in the oxidized zones of lead ore deposits. It is a very common weathering product of galena and other ore minerals.
 
Habitat:                         Habitat: Commonly twinned, often as sixlings. Single crystals are usually tabular and elongated along the a-axis; also equant, rarely acicular or thin tabular. As clusters of crystals, reticulated masses, or “jackstraw” aggregates. Crystals are often striated.
 
Composition:    Leadcarbonate   PbCO3
 
Cerussite also ranks as one of my favourite minerals. The reason for this is simple….it contains almost 80% lead and you can see right through it…how cool and amazing is that!
 
Cerussite is an “old” mineral and knowledge of its existence dates back to 400 BC. The name is derived from the Latin word cerussa, meaning white lead. Cerussa nativa was mentioned by Conrad Gessner in 1565 and in 1832 F. S. Beudant applied the name cruse to the mineral, whilst the present name is accredited to W. Haidinger (1845). In early use it was referred to by the miners as lead-spar and white-lead-ore.
It is found in considerable quantities and its lead contents can be as high as 77.5 %. Its industrial uses include ore of lead and often also of silver. “White lead” is the key ingredient in (now discontinued) lead paints. Ingestion of lead-based paint chips is the most common cause of lead poisoning in children. Both “white lead” and lead acetate have been used in cosmetics throughout history, although this practice has ceased in Western Countries. It is, therefore, recommended to wash your hands after handling it and avoid inhaling dust when breaking it. Also learn from my personal experience; never wash specimens and place them outside in direct sunlight in the middle of the day….they will crack and break. Also never wash specimens in water that is too hot or too cold.
 
 
Cerussite very frequently is twinned, the compound crystal being pseudo-hexagonal in form. Three crystals are usually twinned together on two faces of the prism, producing six-rayed stellate groups with individual crystals intercrossing at angles of nearly 60°. Crystals are of frequent occurrence and they usually have very bright and smooth faces.
 
The type locality for this mineral is Vicenza Province in Italy. Worldwide localities include U.S.A, Zambia, Morocco, New Zealand, Sardinia, Scotland, Germany, England, Australia, Czech Republic, South Africa and of course the Tsumeb mine in Namibia.
 
Cerussite specimens from Tsumeb vary greatly in form, colour and associations. Besides azurite, it is probably the most famous mineral from this locality. In the first oxidation zone the finest examples occurred between 150 to 250 metres. As with anglesite, crystals were not found deeper than 400 metres in the first oxidation zone, but again in the other zones. Tsumeb cerussites break all records with reference to size, beauty and crystallisation. The largest reported crystals were up to 60 cm in length. It was so common and abundant during the seventies that dealers sold perfect gemmy crystals for as little as 1 to 2 US dollars each. Back then the South African Rand was a much stronger currency than it is today so it was really cheap.
 
The colour of Tsumeb cerussites ranges from colourless, yellow, green, brown, red, to black. A green colour is due to the inclusions of malachite and superb green crystals of up to 5 cm were found. A few of these remarkable crystals even contain green phantoms. Gray phantoms are formed by inclusions of galena and red cerussites have inclusions of cuprite.  
Although cerussite and azurite are both carbonates, they rarely occur together on the same specimens, but when they do, the one compliments the specific beauty of the other. Occasionally heart-like twins can be seen on specimens, such as those associated with the azurite from the Easter Pocket. A rare association with dioptase was also found on the 30th level. The Houston Museum has an extraordinary specimen of this combination.
 
The last find of notable specimens from Tsumeb in 1996 was a limited suite of carmine red cerussite crystals up to 2 cm from the third oxidation zone. They provided a wonderful contrast to the associated green malachite. This was the swansong befitting Tsumeb, providing the last minerals that belong to a unique kind.   JDJ
 
All Cerussites from Tsumeb, Namibia. Specimens and photos by J. de Jongh
 
References
Gebhard, Georg, (1999) – Tsumeb II.
Roberts, Campbell, Rupp, (1990) – Encyclopedia of Minerals Second Edition.
The Mineralogical Record, (1977), Tsumeb!