126 



8466, Boulder Perseverance Mine, Kalgoorlie, "West Aus- 

 tralia : caJaverite. 



8762 (and others), Australia Mine, Kalgoorlie; a massive piece 

 of calaverite showing the pale-brass colour of the mineral well. 

 Pieces like this contain about 45 per cent. o£ gold and 1 per 

 cent, of silver. 



8430, Australia Mine, Kalgoorlie. 



Sylvanite. Telluride of gold and silver. Called grapliic tellurium, on 



account of the crystals often having a linear arrangement, 

 somewhat resembling writing. 



8622, Cripple Creek : rich ore with purple fluor. 

 8625-7, Cripple Creek : roasted ore from which gold has been 

 sweated out. 

 Kalgoorlite. A telluride of gold and mercury. 8761, Kalgoorlie. 



Tetradymite. Bismuth telluride. 8522, Duuallan Mine, Coolgardie ; with 

 quartz. 



Case 92. KARE ELEMENTS. 



AUanite. A variety of epidote containing cerium. 6968, Amherst 



County, Virginia. 

 Cerite. Silicate of cerium with lanthanum &c. 3056, Sweden. 



Columbite. Columbate and tantalate of iron and manganese. 3455, 



Amelia, Virginia. 



Microlite. Tantalate of lime. 3476, Amelia, Virginia. 



Monazite. Phosphate of cerium, thorium, &c. 



The mantles used in incandescent gas lamps are now made lai'gely of 

 oxide of thorium ; consequently, varieties of monazite, containing 

 an appreciable percentage of this substance, are in some demand. 

 Monazite-bearing sands are not of exceptional rarity, but the 

 proportion of thorium present is sometimes low. It is jDrocured 

 principally from the Atlantic States of North and South America. 



Monazite is resinous in appearance, brownish in colour, and can be 

 scratched with the point of a knife. The specific gravity (5, or a 

 little over) is of great assistance in determining the mineral. 



3445, Amelia, Virginia. 7713, Delegate Eiver, Victoria : 

 sand. 



