BY W, F. PETTERD, C.M.Z.S. 109 



subjected to the influence of meteoric waters. At the Vale 

 of Belvoir remarkably-shaped worm-like and other fantastic 

 concretionary forms are abundant. In cavernous vughs 

 which are occasionally met with in mines, such as have 

 occurred in the gossanous upper workings of the Hercules 

 Mine, limonite is not infrequently found in stalactitic 

 forms, pointing to its deposition from surface waters. 

 These are sometimes of considerable length, and are 

 not rarely blackened by manganese hydrate. More 

 rarely they are more or less coated with minute crys- 

 tals of mimetite, and even still more rarely they are orna- 

 mented with blebs of dundasite and crystals of cerussite, 

 which scintillate when seen by artificial light. This 

 mineral forms in most part what is commonly known as 

 " bog-iron ore," generally containing more or less man- 

 ganese ; and occasionally a fibrous structure is developed, 

 as is sometimes seen in lode outcrops. What is known as 

 " ochre " is this mineral mixed with aluminous material. 

 In this form it becomes a valuable substance, used as a 

 colouring medium in the manufacture of paint. This iron 

 ochre is fairly abundant in many localities, and is reported 

 to be industrially worked near Carlton. Limonite in 

 irregular elongated cylindrical forms is abundant in the 

 recent clays used for brick manufacture in the vicinity of 

 Launceston. These have been mistaken for fossilised por- 

 tions of trees, organic remains, and even for reptiles. 



At Mt. Lyell blocks of concretionary limonite which are 

 hollow often contain implanted crystals of cuprite. Speci- 

 mens have been obtained showing exceptionally well-formed 

 crystals of this mineral, which are occasionally of a remark- 

 ably large size for the species. At the Dundas Extended, 

 Adelaide, Magnet, and Whyte River silver-lead mines 

 magnificent samples of crocoisite have been obtained pene- 

 trating and implanted upon limonite in association with 

 manganese oxides. It may be remarked that chalcophan- 

 ite, cerussite, gibbsite, and other well-known minerals are 

 commonly similarly connected, which occurrences are 

 referred to under their respective heads. Native copper 

 has been found associated with this mineral at the Rocky 

 River and in the vicinity of Mt. Lyell ; and native silver 

 in capillary masses has been collected at several mines at 

 Zeehan, at the Murchison Mine at Mt. Farrell, as well as 

 other finds of a similar nature of less importance. At the 

 celebrated Bischoff mines it forms the major portion of 

 that part of the mine known as the " Brown Face," which 

 was beyond reasonable doubt a huge mass of pyrites con- 



