42 Assay and Analysis of an Iron Ore. 



Akt. IV. — Assay and Analysis of an Iron Ore, (fer titanne,) from 

 the environs of Baltimore,'^ received through Mr. Warden; hy 



T. G. CLEMSON.f 



From the specimens received, this mineral appears to be associa- 

 ted with a schiste granitoide. Tt is in amorphous masses, possessing a 

 parallel division. The exterior surface is of a reddish brown, like the 

 peroxide of iron. The interior is of a bright gray, having the tex- 

 ture of iron, occasionally presenting indices of crystallization. It 

 feebly attracts small particles of iron, and possesses polarity in a 

 slight degree. Specific gravity =4.9. 



The following assay was made upon a specimen that appeared to 

 be void of gangue. The powder was black, with a tinge of red, 

 which indicates the presence of the peroxide of iron. 



Calcined in close vessels, it does not sensibly diminish in weight. 

 Twenty grains of this mineral were mixed with ten grains of kaolin, 

 (silicate of alumine,) and seven grains of carbonate of lime. The 

 mixture was submitted, in a crucible, to the strongest heat of a wind 

 furnace. The result of the assay was a culot and scorias, weigh- 

 ing in sum, 29.62. The scoriae were covered with a thin metallic 

 layer, of a copper red, which characterises the presence of the 

 oxide of titanium. The interior of the scoriee was nitrous, black 

 and opake. The iron was white, possessing good properties. It 

 weighed, 12. 



Weight of the culot and scoriae, _ _ _ 29.62 



Ten grains of kaolin, calcined, equals, - 10. 



Seven grains of carbonate of lime, - 3.94 



Twenty grains of mineral, _ _ _ 20. =33.94 



Oxygen, -------- 4.32 



13.94 equals the quantity of kaolin and lime added. Now the scorije 

 weigh 17.62. Consequently the kaolin and lime have augmented in 

 w^eight equal to 3.68. 



* Land of Mr. Patterson. 



t Extract of a letter from Mr. T. G. CJemson to the Editor, dated Paris, 

 Maif 27, 1829. 

 I embrace this opportunily of sending you an extract of a process A^erbal, made 

 by myself, at tiie Scliool of Mines, May 1st, 1S29. Considering it of sutBcient in- 

 terest, will you have the goodness to give it a place in the next number of your ex- 

 cellent Journal of Science and Arts. 



