506 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 48. 



The chromium present is tabulated as chromite, as it occurs as 

 such in the stone. No barium, strontium, zirconium or potassium 

 could be detected by analysis. 



The metallic portion freed from the last trace of siliceous matter 

 contained: 



Per cent. 



Iron, Fe .85.00 



Nickel, Ni 14. 15 



Cobalt, Co 0. 74 



Copper, Cu Trace. 



99.89 



On recalculating, these figures give the bulk or mass composition 

 of the stone as follows: 



Per cent. 



Silica, Si0 2 38. 70 



Alumina, A1 2 3 4. 39 



Ferrous oxide, FeO 16. 18 



Manganous oxide, MnO 0. 336 



Nickel oxide, NiO 0. 204 



Lime, CaO 1.939 



Magnesia, MgO 26. 018 



Chromite, FeO.Cr 2 3 0. 708 



Metallic iron, Fe 9. 724 



Metallic nickel, Ni 1. 618 



Metallic cobalt, Co 0. 084 



Total 99. 901 



With traces of sulphur and soda but none of barium, strontium, 

 zirconium, or potassium. Specific gravity, 3.37. Following Bre- 

 zina's classification the stone would be placed in the group of inter- 

 mediate chondrites Ci, or perhaps Cia, as one cut surface shows a 

 small threadlike black vein. 



EXPLANATION OF PLATE 29. 



Fig. 1. The 1,300-gram piece in the United States National Museum, Cat. No. 212. 

 2. The 4,340-gram piece in the museum of the University of Minnesota. 

 In both figures the areas marked "A" show the earliest formed crust, the other 

 pitted surfaces, the secondary and tertiary crusts. 



