266 Proceedings of the Royal Society of Victoria. 



Pseudoniorphous crystals after iolite, accompanied by quartz 

 and felspar crystals from a cavity in granite, Bradford, 

 near Maldon (J. Hornsby). 



Greyish-white matted scales from a quartz reef, Eaglehawk 

 (B.M.). 

 Platinum. — 



Some examples examined were reported by Mr. W. Paterson, 

 of the Bank of Victoria, to occur at Turton's Creek, 

 Gippsland, Avith gold and osmiridium (R.). 

 Plessite. — See note under taenite. 

 Prehnite.* — Hydrous silicate of aluminium and calcium. 



In removing some calcite from a specimen of axinite from 

 Dookie, by dilute hydrochloric acid, a few white crystals 

 of prehnite were revealed. They are very thin and 

 fragile, with broken outline and faces marked with cross 

 striations. The mineral occurs in diorite, and is asso- 

 ciated with axinite, garnet and calcite. A dull green 

 acute angled crystal was likewise noticed, which .can 

 probably also be referred to this species. It was 

 surrounded by a fine fibrous amphibole like byssolite 

 (W). 

 PsiLOMELANE. — Composition varied, but mostly manganese oxide. 



Veins in silurian slate, McKenzie's Diggings, Goulburn ; 

 solid dendrites in a quartz boulder, Chinaman's Flat, 

 Maryborough (B.M.). 



Botryoidal forms incrusting quai'tz, Ararat* (W.). 

 Pyrargyrite.§ — Sulphantimonite of silver. 



Democrat Mine, Glen Wills (CI.). 

 Pyrite. — Iron disulphide. 



Cubical crystals densely impregnating orthoclase, Ararat ; 

 small veins of secondai-y origin in metamorphic sand- 

 stone, Kensington Street Sewer, South Yarra ; nodule 

 of radiated structure from decomposed granite, William 

 Street Sewer, South Yarra (W.). 



Pyrite is so widely distributed that no record has been kept 

 of its occurrence in quartz reefs. It may almost be 

 said that where these are found, so also will pyrite be 

 found in more or less quantity, and even in quartz 

 which has every appearance of being quite pure, this 

 mineral will reveal itself in many instances after 



