We
are pleased to inform you that the mineral coronadite has just been identified
at the Rosh Pinah Zinc Mine for the first time.
It is a predominantly lead based mineral with the
formula Pb (Mn4+, Mn3+)8O16. It is monoclinic, with a
hardness of 4½-5, and a member of the Cryptomelane Group. Its morphology is
massive, with boytroidal crusts with a fibrous structure. It was first
identified as a mineral in 1904, and is named after Francisco Vasquez de
Coronado (ca. 1500-1554), the first Spanish explorer of the American southwest.
Acknowledgment
for identification of coronadite goes to Dr Barbara Cavalazzi who used the
Assore Raman instrument and the SEM at the University of Johannesburg’s Geology
Department, and Dr Sabine Verryn of XRD Analytical and Consulting cc, who
provided XRD analyses to identify the coronadite. Thank you also to Bruce
Cairncross, Allan Fraser, and Gisela Hinder for giving us permission to print
this information.