ORDER ix. NATIVE TELLURIUM. 425 



= 115 12'. Cleavage in various directions, 



which have not been ascertained. 

 Lustre metallic. Colour tin-white. Streak un 



changed. 

 Rather brittle. Hardness = 2-0 ... 2-5. Sp. Gr. 



= 6-115, KLAPROTH. 



Compound Varieties. Massive : composition 

 distinctly granular, individuals small ; sometimes a 

 tendency to columnar composition. 



OBSERVATIONS. 



1. According to KLAPROTH, the native Tellurium con- 

 sists of 



Tellurium 92-55. 



Iron 7'20. 



Gold 0-25. 



It melts easily upon charcoal before the blowpipe, burns 

 with a greenish flame, and is volatilised. The odour of 

 horse-raddish, which some varieties exhale, as has been ob- 

 served by BEHZELIUS, is owing to selenium, and not to 

 tellurium. 



2. The native Tellurium occurs in sandstone probably 

 in beds, or in veins which are of contemporaneous forma- 

 tion with the rock. It is accompanied by rhombohedral 

 Quartz and hexahedral Iron-pyrites, also by hexahedral 

 Gold, particularly that variety in dust-like particles which is 

 known among the collectors and mineral dealers in the 

 Austrian states by the name of Spanish Snuff. 



3. It has been found in pretty considerable quantities in 

 the mine of Maria Loretto at Facebay near Zalathna in 

 Transylvania. It is very rare at present. It was melted 

 in order to extract the proportion of gold which it contains. 



