SMELTING OF CUPREOUS PYRITES. 5 J 



VII 



Account of the Metallurgic Treatment of Pi/riious Copper at 

 the JMiues of Clie.^sy and Sainbel, in t/ni Department of the 

 Rhone: ^// i)/r. Gueniveau*. 



JL HIS paper contains several results of the analysis of th'e Products of th(> 



nietallurcfic products of the works at Chess^^ which appear ^^'^^^^^^tniht 



calculated to serve as bases for the theory ofsmeltin'o^ copper tlieoryof smel- 



i)vrites, and particularly to show the effect of quartz added tmg copper py- 



, . , . . rni f> 1 • • ntes, and the 



to the ore HI tins operation. The fifth part is employed in eftectofquartzj 



describing those chemical operations, that afforded new re- 

 sults ; and the remainder in deriving from those results the 

 most remarkable consequences, and pointing out their ap- 

 plication. 



The chemical experiments were made in part at the la- in concert with 

 boratory of the School of Mining of Mont Blanc, under the ^^ Descotlls 

 inspection of Mr. Hassenfratz, and partly at the laboratory 

 of the Council of Mines, under Mr. Descotils. 



The metallurgic products subjected to analysis were sco- They were the 

 rite from the pyritous copper, taken from the basin of the ^^^"^ a ^/!l^ 

 fore hearth during the operation. Of these there are two matts. 

 sorts, one formed during the fusion of the roasted ore, the characters of 

 other during that of the roasted matts. The first sort is of a the 1st, 

 tolerably brilliant metallic gray colour ; exhibits laminae, 

 indicating a crystallization ; and may easily be confounded 

 with certain ores of oxidulous iron. The second has no me- o^ ^^^ 2d, 

 tallic lustre, is of a brown colour, and of a fibrous fracture. 

 The characters common to both are, they are tolerably com- common t« 

 pact, without any vitreous appearance, and almost without °^ * 

 blebs ; attractable by the magnet ; melt before the blow- 

 pipe without addition, sometimes emitting a slight smell of 

 sulphur, and with borax exhibiting the same characters as 

 iron ores; yielding iron when assayed in the dry way, and 

 sometimes traces of copper ; and forming a jelly with acids 

 with great facilit}'. 



The following is a general description of the mode in General mode 

 which they were analysed. After they were powdered, they ° ^" ^^"^' 



• Abridged from the Journal des Mines, Oct. 1806, Vol. xx, p. 245. 



E 2 were 



