THE NONMETALLIC MINERALS. 419 



In New South Wales the material is commonly met with as an efflor- 

 escence in caves and under sheltered ledges of the Coal Measure sand- 

 stone, usually with epsomite, as at Dabee, County Phillip; Wallera- 

 wang- and Mudgee road, County Cook; the mouth of the Shoalhaven 

 River, and other places. Also found in the crevices of a blue slate at 

 Alum Creek, and at the Gibraltar Rock, County Argyle. Occurs as a 

 deposit, with various other salts, from the vents at Mount Wingen, 

 County Brisbane, together with native sulphur in small quantities; and 

 at Appin, Bulli, and Pitt Water, County Cumberland. At Cullen 

 Bullen, in the Turon district, County Roxburgh; at Tarcutta, County 

 Wynyard; Manero; Wingello Siding, and Capertee. 



A specimen in the form of fibrous masses, made up of long, acicular 

 crystals, white, silky luster, like satin spar, found as an efflorescence in 

 a sandstone cave near Wallerawang, was found to have the following 

 composition : 



Water 47. 585 



Matter insoluble in water 1. 079 



Alumina 15. 198 



Sulphuric acid 34. 635 



Soda .931 



Potash 337 



Loss... .235 



100. 000 



The formula for the above is practically A1 2 O 3 .3SO 3 +18H 2 O. An- 

 other specimen from the same place was found to contain a notable 

 quantity of magnesium sulphate. 



Water, by difference 47. 388 



Silica 1. 908 



Alumina 13. 113 



Sulphuric acid 33. 067 



Lime 798 



Magnesia 3. 726 



Total 100. 000 



The formula for the above is also practically A1 2 O 3 .3SO 3 +18H 2 O. 

 ALUMINITE. Aluminite is a dull, lusterless earthy, aluminum sul- 

 phate of the composition indicated by the formula A1 2 O 3 .SO 8 ,9H 2 O = 

 sulphur tri oxide 23.3 per cent; alumina 29.6 per cent; water 47.1 per 

 cent. It is soluble only in acids, white in color, opaque, and occurs 

 mainly in beds of Tertiary and more recent clays. 



ALLTNITE. Composition K 2 0. 3 A1 2 O 3 .4SO 3 ,6H 2 O= sulphur trioxide 

 38.6 per cent; alumina 37.0 per cent; potash 11.4 per cent; water 13.0 

 per cent. Hardness 3. 5 to 4; specific gravity 2. 58 to 2. 75. This mineral 

 occurs native in the form of a fibrous, or compact finely granular rock 

 of a dull luster somewhat resembling certain varieties of aluminous 

 limestones. It is infusible and soluble only in sulphuric acid. The 

 more compact varieties are so hard and tough as to be used for mill- 



