author(s) : Lehmann
date of publication : 1874
source : Jahrb. fuer Min. p.273
formula : Ca6Al2((OH)4 SO4)3 24H2O
comments about the origin : etiquette Bertrand coll.Adam No5701 obtenu par Bertrand en 1879 (prov. coll. Lehmann, 1873)
This type specimen, kept in the Museum of Ecole des mines de Paris, has been indexed by Dr Guillemin.
(C) BRGM, ENSMP