Summary: A new occurrence of varlamoffite is described, and the status of this species is considered; the term is best employed for cryptocrystalline 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, CaSnSiO₅, is briefly described; it is isostructural with sphene.