Proposal 2004-051, hydrous alumina, was approved by the CNMMN (see publications ‘Minerals approved in 2004). Several CNMMN members had asked, however, for a reexamination of akdalaite (IMA1969-002) which was approved as the first natural hydrous alumina.
The authors of IMA2004-051 obtained holotype material of akdalaite from the Fersman museum in Moscow, and the re-examination showed that akdalaite and the material for IMA2004-051 are identical. The previously refined unit cell of akdalaite is incorrect, so that akdalaite and IMA2004-051 are actually the same mineral species. The name ‘akdalaite’ has priority; the fact that akdalaite was given a wrong space group does not necessitate a formal redefinition of this mineral. The re-examination and IMA2004-051 should be published as “New data and a new occurrence of akdalaite”. The approval decision of the CNMMN on IMA2004-051 is consequently nullified.
