Director of Geological Survey, Malaya,

Summary. A new occurrence of varlamoffite is described, and the status of this species is considered; the term is best employed for eryptoerystalline yellowish material consisting predominantly of Sn and H20 that may yield a diffuse powder pattern comparable to, or closely resembling that of cassiterite, but does yield a powder pattern identical with that of cassiterite after heat-treatment at about 1200 ~ C. A new mineral, malayaite, CaSnSiQ, is briefly described; it is iso-structural with sphene. I N January 1953, a fragment of a cassiterite crystal coated with a pale lemon, soft, amorphous material, obviously derived therefrom, was presented by Mr. J. D. Hellings of Messrs. Osborne and Chappel (Mining and Consulting Engineers), to the Director of Geological Survey, Federation of Malaya. The specimen (no. 19384) came from an open-cast mine (lat. 4 ~ 15~ ' N., long. 101 ~ 14 ' E.) in the valley of the Sungei Lah, Chenderiang, Perak. Chenfical analysis by Mr. W. A. Tooke of a very small quantity of the specimen indicated that it was a hydrated oxide of tin and the sample, which was not reduced to Sn when treated with hydrochloric acid in a zinc dish, was thought to be varlamofilte. Additional specimens (19384-A to F) were collected by Fl inter in January 1953; others (grouped as 19384-G) were supplied by Messrs. Osborne and Chappel in October 1954 and July 1955; all these specimens were recovered from clays (in some places notably reddish) lying in north-south trending troughs between caps of limestone in Mining Lease No. 2485. Flinter collected other specimens (grouped as 18951 and]8951-A) which he found scattered, together with diaspore, in alluvium lying above limestone near a north-south granite/limestone 1 Compiled from material included in a cyclostyled circular issued by the Direc-tor of the Geological Survey, Malaysia, for internal distribution. VAR, LAM OI~I~ITE 623 contact exposed in the Kean Sang Mine No. 2 (lat. 4 ~ 1489 N., long. 101