22 THE MINERALS OF TASMANIA. 



37. Basanite ( A Variety of Si O^J. 



This is the lydian or touchstone, a compact black quartz. 

 The stone was used for testing the quality of gold by rub- 

 bing that metal upon a smooth surface, the colour of the 

 istreak indicating the amount of impurity. 



Localities : Swansea, Conara, and other places. 



38. Bastite. (See Schiller Spar.) 



39. Batchelorite (Hydrated Silicate of Aluminium). 

 This apparently new substance is, so far as known, 



always massive, without any indication of crystallisation. 

 It has an indistinct cleavage, is imperfectly foliated, and 

 slaty in general appearance. In feel it is remarkably 

 smooth, and inclined to be unctuous. The colour is invari- 

 ably a shade of green, from what may be termed a pale 

 apple-green to greenish-grey. Lustre glimmering to shin- 

 ing, with an oily appearance on the smoother surfaces. 

 It is translucent in thin flakes. Streak, white. Hard- 

 ness = 4. Specific gravity = 3'3. 



Analysis by G. F. Beardsley (as green nodules in 

 schist) : — 



101 1 



Answering to the formula — 



H,0 M, O3, Q Si 0, 

 (J. W. Gregory, Aus. Inst. Min. En., 1905.) 



This is the substance which has been known as pyrophyl- 

 lite (Catalogue of the Minerals of Tasmania, 1896, page 

 72, No. 207). It has also been termed agalmatolite. It 

 is generally known on the Mt. Lyell mining field as " green 

 schist," and also perhaps more commonly as serpentine, or 

 even as " greenstone." As it takes a fairly high polish it 

 has been used, to a limited extent, as watch-chain pend- 

 ants. Professor Gregory remarks (loc. cit.) " that it is 

 not a bisilicate such as pyrophyllite." It has been named 

 in memory of the late Mr. W. T. Batchelor, at one time 

 mine manager of the Mt. Lyell Mine, to whom the writer 

 is indebted for many interesting mineral specimens, includ- 

 ing excellent examples of this substance in particular. 

 It is said to occur on one of the walls of the enormous 



