XX 



1898. 



MAY. 

 The first meeting of the 1895 session of the Royal Society of 

 Tasmania |was held in the Art Gallery, Museum, on Tuesday, May 

 20th. There was a very large attendance, Sir James Aguew occu- 

 pying the chair in the absence of His Excellency the Governor, who 

 had a prior engagement. 



The following papers were taken as read : — 



" Notes on a Mineral Substance New to Tasmania," by Mr. W. 

 F. Petterd :— During a recent visit to the Zeehan silver-field my 

 attention was drawn to a peculiarly coloured and unusual form of 

 pyrites occurring in one cf the silver-lead lodes on the property of 

 the Silver Queen Prospecting Association. It is found in some 

 quantity, both massive and disseminated, closely associated with 

 various other forms of pyrites and richly argentiferous galena in a 

 portion of this particular lode, locally known as "Clarke's Tribute." 

 tn colour it is of an unusual greenish grey with a bronze-like highly 

 metallic lustre, but is sometimes inclined to brass yellow from extreme 

 admixture of chalcopyrite. It is very brittle, with an uneven fracture. 

 Its hardness is about 4, of the scale ; specific gravity, 4 '5. Upon 

 a qualitative analysis by the wet process, and examination with the 

 blowpipe, the substance proves to be a rare mineral known as stannite 

 (a sulpho-stannate of iron and copper), or chemically, 2 Fe, Su 

 S2 + 2 Cu S, Sn S2=S29"77 ; Cu 2977, .Sn 27'44, Fe 13-02 = 100. 

 The mineral is commonly known as " tin prites," or "bell-metal ore," 

 and is almost peculiar to the stanniferous districts of Cornwall, Eng- 

 land, being only rarely found out of its original locality. It has been 

 reported to occur in Bohemia, at Zinnwald, in the Erzgebirge, with 

 blende and galena. In Australia it is reported to occur in extremely 

 limited quantity in the tin districts of New South Wales and Northern 

 Queensland. The finding of this mineral in association with silver-lead 

 is quite unexpected, and very interesting from a scientific point of 

 view, more especially as it is in itself of a high argentiferous value, 

 which is quite a new feature with this chemical compound. I am 

 informed by Mr. J. G. S. Stifct, of Zeehan, that its average silver 

 value is about 90cz. per ton, and that it is readily purchased — mixed 

 with other minerals— by the local ore-buyers. Numerous analyses of 

 stannite from Zinnwald and Cornwall give a metallic tin value of 

 from 25-81 to 31 62 per cent., the copper varying from 23 55 to 30 0, 

 but I am not prepared with information as to the metallurgical value 

 of either metallic constituent as occurring in chemical association. I 

 have submitted samples to Professor G. H. F. Ulrich, of tre Dunedin 

 University, who writes, under date March 30, 1895 : — " The sample 

 of ore is stannite, or bell metal ore, as you supposed. Our lecturer 

 in metallurgy and assaying, Mr. Fitzgerald, made a rough quantitative 

 analysis of the ore, the results of which fall also within the range of 

 the analysis given for stannite in Dana's 'System of Mineralogy,' Its 

 colour, streak, hardness, and indistinct cortical cleavage are also in 

 agreement with those given for the mineral. If the ore occurs in any 

 quantity the respective mine owners would, I think, be wise in getting 

 it picked out for separate sale, with the object of having its contents 

 in copper and tin taken into account in the sale price in addition to 



