85 



Crinnis Mine, Ulricli at the Oratunga Mine, Tate at Eudunda 

 and Burr reports it at Eapid Bay, Barossa Eange, Mount Lofty 

 Range and various other places. It also occurs at the Kar- 

 kulto Mine, whence a specimen has been obtained for examina- 

 tion. It was in the form of a largely crystalline mass of a 

 brownish-grey colour. Hardness, 3*5 ; and specific gravity, 3"9. 

 The analysis of this specimen yielded the following results 

 (i). No. II, introduced for the sake of comparison, is the 

 composition of a specimen from Mitterberg, Tyrol, quoted from 

 Dana : — 



100-00 100-00 

 The composition of the mineral as given above is represented 

 by the formula 4 FeCOg + MgCOg. From the composition 

 of this specimen and from that of others, which have from time 

 to time passed through my hands, it would appear that the 

 siderite of this colony is chiefly of the magnesian variety. 



PiSTOMESITE. 



This mineral occurs in large quantities at the Balhannah 

 Mine, the waste tip being for the most part formed of it. 

 "When first obtained this mineral is of a yellowish-grey colour, 

 but on exposure it assumes a bronze-coloured coating. 



A preliminary examination showed that the mineral consisted 

 of magnesic, ferrous and manganous carbonates, and at first 

 I was inclined to think that it was Breunuerite, a ferriferous 

 variety of Magnesite. A complete quantitative analysis showed, 

 however, that the mineral had the composition of Pistomesite, 

 with which it also agrees in its physical properties. The 

 specimen for examination was selected from the centre of a 

 large mass, and was free from the incrustation referred to 

 above. The result of the analysis was as follows (i), No. ii 

 being the analysis of a specimen from Thurnburg quoted by 

 Dana : — 



99-98 99-26 



*Obtained by difference. 



