88 THE MINERALS OF TASMANIA. 



140. GosLARiTE (Hydrous Sulphate of Zinc). 



This vitriol occurs as small mammillary and investing 

 bunches, which are u_sually stained with iron oxide, in the 

 dry workings of the older mines. It may be detected by 

 its characteristic astringent and nauseous taste. It 

 occurred in some abundance, intermixed with other sul- 

 phates, in an adit at the Blue Tier, near Beaconsfield ; and 

 also at the Comstock Mine, near Zeehan. 



141 Graphite (Plumhago, Carhon). 



Of common occurrence as graphitic slate, of no com- 

 mercial importance. At the silver-lsad mines of Zeehan 

 and Dundas it often occurs in the walls of the lodes more 

 or less intermixed with earthy matter, and more rarely in 

 the cleavages of the ore. In the vicinity of the Ring River 

 a small seam occurs a few inches in thickness. At the 

 North Valley at Bischoff a somewhat loose mass occurred 

 with a high metallic lustre. On the beach about 2 miles 

 west of the Lsven River it is abundant in the form of 

 graphitic schist. It coats the joints of a crystalline lime- 

 stone at the Wilmot River. It is reported to occur in 

 considerable quantity, but of indifferent quality, at Cape 

 Barren Island ; and at the Rocky River Mine. 



142. Grossularite (Calcium- Aluminium Garnet). 



This mineral occurs as a subcrystallised to a somewhat 

 compact rock of a pale olive-green to brown colour, and 

 rather vitreous lustre, near Mt. Claude. What seems to 

 be this species of garnet occurs abundantly in the massive 

 form at the Shepherd and Murphy Mine, Bell Mount, 

 Middlesex. It is of a peculiar yellowish-green colour, very 

 compact and tough, with a vitreous-oily lustre. It often 

 affects an irregular undefined banded habit, and is almost 

 invariably closely intermixed and parallel with an intensely 

 black finely granular magnetite. Both the garnet and the 

 magnetite are traversed by narrow bands of a pink to 

 salmon-coloured wollastonite, and the magnetite may con- 

 tain minute specks of pyrites scattered plentifully through 

 out its substance. At Mayne's Tin Mine, Mt. Heemskirk, 

 this variety of garnet occurs as a narrow seam with closely 

 packed characteristic crystals of a bright-yellowish brown 

 colour. The crystals are very minute, but often well 

 formed. (L. K. Ward). 



