METEORITES OF NORTH AMERICA. 321 



The material analyzed was obtained by treating the metallic portion with mercury bichloride, and after its solu- 

 tion separating the troilite and schreibersite from carbon, silicates, etc., with the magnet and from each other by lixivi- 

 ation. The material thus obtained had a specific gravity of 4.759 at 18° C. and the following composition: 



Iron 62. 99 



Nickel 



Cobalt 



Phosphorus trace 



Sulphur 36. 35 



} .79 



'} 5.039 



100. 13 



The specular material lining the olivine cavities is essentially a graphitic iron containing sulphur and chlorine. 

 The material analyzed was far from being homogeneous, as it was separated mechanically with the aid of a glass. The 

 composition was as follows: 



Iron 84. 900 



Nickel 



Cobalt 



Silica 2. 990 



Carbon 2. 810 



Sulphur 1. 750 



Phosphorus 1. 470 



Chlorine 0. 100 



Alumina 0. 940 



99. 999 



Chromite occurs quite abundantly, varying in size from microscopic grains to a crystal 1 mm. in diameter. The 

 crystals are more or less perfect octahedrons, rarely modified by other forms, and then only by the dodecahedron 

 (110), as noted in one instance. They are brilliant black in color with a metallic luster; nonmagnetic; have a spe- 

 cific gravity of 4.49 at 18° C, with the following composition: 



Chromic oxide 64. 91 



Alumina 9. 85 



Magnesia 4. 96 



Ferrous oxide 17. 97 



Silica 1. 38 



99.07 



Olivine occurs in more or less rounded masses which, when carefully extracted, show well-marked facets. These 

 facets are probably not to be referred to any crystal forms, since no zonal relations could be established after repeated 

 measurements. The mineral is commonly brownish in color and only occasionally honey yellow. The blebs are more 

 or less cracked and the cracks filled with foreign material, as graphitic iron, limonite, chromite, etc. Some of the 

 clearest grains, which under the glass were quite free from impurities, were selected for analysis, with the following 

 results: 



Silica 35. 70 



Magnesia 42. 02 



Ferrous oxide 20. 79 



Ferric oxide 0. 18 



Alumina 0. 42 



Manganese 0. 14 



Nickel oxide 0. 21 



Phosphorus trace 



99.46 



The meteorite is somewhat distributed, but is chiefly in the possession of the U. S. National 

 Museum. 



BIBLIOGRAPHY. 



1. 1903: Merrill. Amer. Geol., vol. 31, pp. 156-158. 



2. 1905: Tassin. Proc. U. S. Nat. Mus., vol. 28, pp. 213-217. 



Muchachos. See Tucson. 



