134 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. XIII. 



BIBLIOGRAPHY. 



1. 1890: Eakins. Meteoric iron from North Carolina. Amer. Journ. Sci., 3d ser., vol. 39, pp. 395-396. (Analysis.) 



2. 1889-1890: Kunz. Meteoric iron from Colfax Township, Rutherford County, North Carolina. Trans. New York 



Acad. Sci., vol. 9, pp. 197-198 (analyses by Cramer). 



Collin County. See Mackinney. 

 Colorado. See Russel Gulch. 

 Concepcion. See Adargas. 

 Coney Fork. See Carthage. 



COON BUTTE. 



Coconino County, Arizona. 



Latitude 35° W N., longitude 111° Y W. 



Stone. Breccialike gray chondrite (Cgb) of Brezina. 



Found 1905; described 1906. 



Weight, 2,789 grams (6 lbs.). 



This meteorite was found by Messrs. D. M. Barringer and S. J. Holsinger on June 24, 1905, 

 about 1 mile west of Coon Butte. It is described by Mallet ' as follows : 



The specimen, as received by me, was pyriform, with a roughly triangular cross section bounded by two approxi- 

 mately flat surfaces (one larger than the other) inclined at about 60° or 65° to each other and united by a third, 

 irregularly curved convex surface. It was a good deal larger at one end than at the other. The general surface was 

 smooth,, but indented at places with the characteristic shallow pittings, like thumb prints on a lump of sculptor's 

 modeling clay, which are seen on so many meteorites. One presumably rather large piece had been broken off 

 from the smaller end, and two other much smaller fractures appeared at and near the larger end. Measuring the mass 

 as it lay on the larger, approximately flat face, the maximum length was about 14.5 cm., maximum width about 11.8 

 cm., and maximum thickness about 8.9 cm. The weight of the specimen as it reached me was 2,789 grams. There 

 is an external oxidized crust, generally of dark, blackish brown color, with patches of redder brown, for the most part 

 very thin, not exceeding 0.5 mm. in thickness; at some points the oxidized material runs in to a depth of 7 or 8 mm. 

 A surface of fracture shows a gray mass of not very well-defined chondritic and brecciated structure, with numerous 

 little spots of iron-stained yellowish brown color, including lustrous points of metallic iron; the general appearance 

 like that of the Pultusk meteorites of January 30, 1868, but without the glossy black crust of these stones. There is 

 a still closer resemblance, both of crust and fractured surface, to the meteorites from Ness County, Kansas. From the 

 general appearance of the surface of fracture, I am inclined to class this specimen as Brezina's breccialike gray chon- 

 drite (Cgb). The specific gravity of the whole mass, taken by suspension in water at 15° C, was found to be 3.471, 

 which is sensibly less than the results of calculation from the constituent materials found by analysis, indicating some 

 lack of compactness in structure. 



George P. Merrill, head curator of geology at the U. S. National Museum, who has given much attention to the 

 petrographic study of meteorites, very kindly undertook to have thin sections made of some fragments I sent him, to 

 examine these under the microscope, and to secure photomicrographs of some of them. The notes with which he has 

 favored me are as follows: 



"Aside from its metallic constituents, the stone consists mainly of enstatite and olivine. The enstatite, which 

 is largely in excess, occurs in granular form without distinct crystal outlines and also in chondrules of the usual fan- 

 shaped radiating and granular structures. In the larger forms of the single crystals a condition of molecular strain is 

 manifested by the manner in which, between crossed nicols, the dark wave sweeps over the surface. Such a con- 

 dition, it may be stated, is not uncommon in stony meteorites, though its full significance seems not to have been 

 realized. 



"The olivine likewise occurs in granular form and in that of chondrules with the characteristic barred or grate- 

 like and, more rarely, porphyritic structures. Except where stained by a recent oxidation of the ferruginous con- 

 stituents, both minerals are colorless or but slightly gray. 



"In addition to the mineral above described, is a completely colorless isotropic substance occurring, as a rule, 

 with no crystal outlines, but rather filling interspaces as would an interstitial glass. It is sometimes quite free from 

 inclosures or, again, includes numerous silicate granules and opaque metallic particles. Rarely does it show any- 

 thing suggestive of cleavage. Excepting in its lack of crystallographic outlines, the mineral is similar in all respects, 

 as far as appearance goes, to the maskelynite of the Shergotty (India) meteorite, and such I shall have to assume it to 

 be. It is altogether too small in amount to permit a satisfactory chemical determination, though with more material 

 a microchemical test might be made which would go a long way toward settling the problem. 



"The chondritic structure of the stone is not strongly marked, and the individual chondrules are themselves 

 almost invariably of a fragmental nature. The structure, as a whole, is not unlike that of the Ness County, Kansas, 



