82 BULLETIN 9i, UNITED STATES NATIONAL MUSEUM. 



Recalculated, these results give the following, showing the com- 

 position of the stone as a whole : 



Per cent. 



Silica (SiOj) 36.68 



Alumina (AUOs) 3.76 



Ferrous oxide (FeO) 19.11 



Lime (CaO) 2.10 



Magnesia (MgO) 25.46 



Manganous oxide (MnO) .22 



Nickel oxide (NiO) .07 



Nickel (Nl) -42 



Cobalt (Co) -03 



Copper (Cu) -01 



Iron (Fe) 4.39 



Ferrous sulphide (FeS) 7.56 



99.81 

 The sulphide separated mechanically yielded: 



Per cent. 



Iron 63. 62 



Sulphur 36. 50 



100.12 



Specific gravity, 4.61. 



These results show the mineral to be troilite and not pyrrhotite. 

 Gifts of F. C. Chekal and C. S. Bement. 



References.— G. P. Merrill, Smithsonian Misc. Coll., vol. 60, No. 9, 

 1912. W. M. Foote, Amer. Journ. Sci., vol. 34, 1912, pp. 437-456. 



HOLLAND'S STORE, CHATTOOGA COUNTY, GEORGIA. Nos. 127, 304. 



Iron Hb. Weight, 142 grams. Thin triangular slice, etched, and 

 showing granular structure, weight, 122 grams, and fragment weigh- 

 ing 20 grams. Found 1887 ; date of fall unknown. AVeight of origi- 

 nal mass 12.5 kilos (27 pounds). Analysis by Wliitfield showed: 



Per cent. 



Iron (Fe) 94. GO 



Nickel (Ni) 4.97 



Cobalt (Co) -21 



Phosphorus (P) -21 



99.99 

 Chlorine and sulphur present, but not determined. Specific grav- 

 ity, 7.801. This iron belongs to the hexahedrite group of Brezina, 

 and shows the fine markings due to twinning, known as Neumann 

 lines. 



Reference.— G. F. Kunz, Amer. Journ. Sci., vol. 34, 1887, p. 471. 



HOMESTEAD, IOWA COUNTY, IOWA. Nos. 11, 21, 423. 



Stone, Cgb. Complete individual with dull black, somewhat 

 blebby crust, weighing 322 grams; fragments, weighing 79 and 230 



