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Analysis of a New Mineral found in the Paramo Rico, near 

 Pamplona, South America. By M. J. B. Boussingault. 



At a small distance from the village Montuosa-Baja, in the 

 Paramo Rico, S800 metres (12,467 English feet) above the level 

 of the sea, there is found, in a decomposed syenite, a yellow- 

 heavy substance, which, from my analysis, seems to form a new 

 mineral species. 



This mineral occurs in small concretions, has a yellow colour, 

 verging towards green, and a specific gravity = 6.00, that of 

 water at the temperature of 24° C. (75° F.) being taken as unity. 

 Before the blowpipe, on charcoal, it melts with ease into a dark 

 coloured globule. With soda we obtain a particle of lead, but 

 which is immediately changed into an infusible slag. After a 

 new addition of soda, the slag sinks into the charcoal. On the 

 mass being pulverized and washed, we obtain a grey, heavy, 

 metallic powder, which has the aspect of regular molybdenum. 

 This is also proved via ?iumida, by which we get a considerable 

 quantity of molybdic acid. This mineral is soluble with effer- 

 vescence in nitric acid ; and the solution is precipitated by nitrate 

 of silver. It is quickly acted on by hydrochloric acid ; there is 

 formed hydrochlorate of lead, and the solution becomes of a 

 green colour ; at the same time is disengaged an odour of chlo- 

 rine. 



When I had thus ascertained that the mineral of Pamplona 

 consisted of lead in combination with molybdenum, carbonic, 

 hydrochloric, and chromic acids, I proceeded as follows to its 

 analysis. One hundred grains of the powdered mineral were at 

 first brought to incipient red heat. This separated 2.9 grains 

 of carbonic acid. 



The roasted mineral was dissolved in nitric acid, diluted with 

 six times its volume of water. The solution was dull yellow, 

 and there remained undissolved 3.7 grains of silica. 



The addition of sulphuric acid to the nitric solution precipi- 

 tated sulphate of the oxide of lead, which, after a red heat, 

 weighed 95.9 grains, corresponding to 76.6 grains of oxide of 

 lead. 



