76 THE MINERALS OF TASMANIA. 



for the mineral collector; its diversified topographical char- 

 acter, with numerous mountains and valleys, affords special 

 facilities for the prospector and miner, while its geology 

 offers the wide range of the crystalline quartzite and schists 

 of the Archaean and Silurian epochs to the Tertiary and. 

 Recent formations. In addition, the Island presents an al- 

 most boundless variety of igneous rocks, ranging from the 

 older and almost indecipherable f el sites to the effusive 

 melilite and normal basalt, with their varieties. 



A prominent feature on the North- West and North-East 

 and granite bosses, enclosing pegmatite dykes and elvan 

 courses, which afford the minerals peculiar to these acidic 

 rocks. The serpentine intrusions of the North and North- 

 West add diversity to the region available to the mineral- 

 ogist, while the apparently intrusive Mesozoic dolerite, 

 which claims so large an extent of the Island, is not an 

 altogether barren field for the ardent mineral collector. On 

 almost every side something great or small will be found 

 worthy of attention, and, should the excursion be extended 

 to the northern portion of the State, the most advanced 

 enthusiast may rest assured that ample scope Vv-ill be found 

 for hammer and bag, wnth every reasonable certainty of his 

 being able to add to the cabinet specimens both rare in 

 nature and fine in quality. 



Concise Retrospect of the More Important and Interesting 

 Minerals Known to Occur. 



Among the native elements may be mentioned the beauti- 

 fully-crystallised alluvial masses of gold which have been 

 and still are occasionally obtained in the district immedi- 

 ately west of the mining township of Waratah. Native 

 bismiith occurs, disseminated through a hornblende matrix, 

 at Mount Ramsay, and, in association with fluor, wolframite, 

 and chalcopyrite, at Mount Black, and a mass, weighing 

 55 lbs., was obtained near Weldborough in alluvial tin-drift. 

 Native copper is found, as foil of extreme tenuity, in the 

 cleavages of the killas, or slate, adjacent to the cele-brated 

 Mount Bischoff Mine, and is abundant in the form of arbor- 

 escent masses about Mount Lyell ; in fact, at one locality 

 it has been worked as an ore of the metal. Native silver 

 occurs at several of the Zeehan and Heazlewood mines, and 

 some remarkably beautiful examples have occasionally come 

 to light. Sulphur has been obtained in some quantity in 

 the Mount Bischoff workings, and a limited dusting of this 

 element has been observed on some of the galenite won at 



