374 CharaBers tf the nno Meta!, Telliiriunt' 



12. A very pure prufliate of potafh occafions no precipitate in the folutions of this 

 metal. This is a remarkable exception to the general rule of metallic precipitations j 

 which, however, it partakes with gold, platina, and antimony. 



13. The alkaline fulphurcts, mixed with the acid folution, occafion a brown orblackiflx 

 precipitafe, accordingly as the metal is combined with more or lefs of oxygen. It fome- 

 timcs happens that the colour of the precipitate perfeQly refembles kerraes mineral, or 

 the red fulphurated oxide of antimony. When the fulphuret of tellurium is expofed on 

 an ignited coal, the metal burns with a blue colour, together with the fulphur. 



14. The infufion of the nut-gall, combined with the fame folutions, affords a precipi- 

 tate in flocks of an Ifabella colour. 



15. Iron and zinc precipitate tellurium from its acid folutions in the metallic ftate, 

 under the, form of fmall black, flocks, which refume the metallic brilliancy when* rubbed, 

 and are fufcd into 4 metallic button upon an ignited coal. 



16. Tin and antimony occafion the fame phenomenon with the acid folutions -of the 

 new metal. The -precipitate formed by antimony proves, in the moft ftriking manner, 

 that tellurium is not antimony difguifed, as had been fuppofed. The folution of tin in 

 the muriatic acid, mixed with a folution of tellurium in the fame acid, likewife produces 

 a black metallic precipitate. 



17. The oxides of tellurium, obtained frOm the acid folutions by alkalis, or from al- 

 kaline folutions by acids, are in either cafe reduced with a degree of rapidity approaching 

 to detonation, by expofure to heat upon charcoal. It burns, and is volatilized, as has^ 

 already been mentioned. 



18. By the application of heat, for a certain time, In a retort, this oxide of telluriura 

 becomes fufed, and, when cold, appears of a flraw colour, with a kind of radiated texture. 



ig. With the addition of any fat fubftance, the oxide of tellurium is pcrfeftly reduci* 

 ble by the method before defcribed. 



The white ore of gold from Fatzhay, aurum vel metallum problematicum, contains, i» 

 loco parts, tellurium in the metallic ftate, 925,5; iron, 72,0; gold, 2,5. 



The graphic gold of OfFenbanya contains, in 100 parts, tellurium in the. metallic- 

 ftate, ^Oj gold, 30 ; filver, 10. 



: The mineral known by the name of the yellow ore of Nagyag contains. In 100 parts,' 

 metallic tellurium, 45,0', gold, 27,0; lead, 19,5 ; filver, 8,5; andof fulphur a minute portioni. 



The mineral known by the name of the grey foliated ore of gold from Nagyag con* 

 tains, in 100 parts, lead, 50; metaUic tellurium, 33 ; gold, 8,5; fulphur, 7,5 }-Ji1yet 

 and copper, i. 



After the above was printed In the Annales de Chimie, the editors of that excellent 

 work received a tranflation of a manufcript addrefl'ed by M. Klaproth to CIt. Van Mons,. 

 on their behalf. From this they extradled the following mineraloglcal and chemical details * n 



The colour of the metallum paradoxum, of the mine of Fatzbay, is between the white of 

 tin and the grey of lead ; it has much metallic brilliancy. It Is fometimes In lumps, and 

 then forms an aggregate of cryftalline grains. Its texture is ufually fine or fmalj grained,. 



* Atm.ales de Chimie, xxv. Ji?... 



Itfr 



