Tsumeb is the Type Locality
Rare. Second and third oxidation zones.
- 2nd Oxidation Zone
- 3rd Oxidation Zone
The type specimen is from the second oxidation zone; probably 30 Level. A second discovery on 44 Level (third oxidation zone) produced many small specimens of ludlockite, some of which were yellow in colour, and included possible pseudomorphs of ludlockite after chalcocite.
Paragenetic and General Notes
The type assemblage comprises ludlockite with zincian siderite and quartz, on a tennantite-chalcocite-germanite-pyrite-bornite matrix.
The 44 Level paragenesis is quite different, with ludlockite associated with leiteite, reinerite, stolzite, and schneiderhöhnite (Gebhard, 1999). Other minerals with which ludlockite is associated include germanite; renierite; stottite and stibioclaudetite.
It is notable that the chemical formula of ludlockite was originally presented as (Fe2+,Pb)As5+2O6 (Embrey et al,. 1977a). However, Cooper and Hawthorne (1996) showed that the arsenic occurs in its intermediate As(III) oxidation state, and that the iron occurs as Fe3+. The correct formula is therefore Pb2+Fe3+4As3+10O22
Ludlockite has been reported to form pseudomorphs after the following minerals: chalcocite (rare).