METEORITES OF NORTH AMERICA. 497 



Cohen u gives the following analysis by Dr. O. Burger: 



=100.02 



The structure of the etching figures is thus described by Brezina: 10 



Lamellae of medium length, straight (except for mechanical deformation), bunched, well defined; kamacite 

 strongly granular, taenite normal. Fields small, filled partly with kamacite-like and strongly granular and partly 

 with dark-gray plessite. Width of the bands, 0.25 mm. 



With Yanhuitlan, Brezina unites an iron obtained from Carl Goldbach, who acquired it 

 from a collection where it had a label stating that it had been brought by Humboldt from 

 Mexico from a meteorite used as an anvil. 



Cohen u describes the etching figures as follows: 



The strongly predominating lamellae are of medium length, straight, and as a rule grouped. The kamacite is 

 composed of grains measuring about 0.1 mm. in cross section, the boundaries of which are more sharply seen the more 

 that they are magnified. Such magnification also shows partly reflecting, partly dull points which probably indicate 

 a further structure of more minute grains. On strong etching the kamacite resolves into a clear, strongly reflecting 

 groundmass in which black, dull particles 0.02 mm. in diameter, of rounded or elongated form lie now isolated, now 

 arranged in parallel lines. Taenite is to be plainly seen only under the microscope so that with the naked eye the 

 lamellae can not be readily distinguished. The fields are abundant and uniformly distributed. They rarely exceed 

 1 sq. mm. in area and are filled as a rule by dark, compact plessite, easily yielding to acids. Glistening spangles 

 can be seen in this under the microscope. These fields are plainly visible but others, commonly larger, can only 

 be distinguished with difficulty. They are made up either of small complete lamellae or of granular kamacite scarcely 

 distinguishable from that of the bands. The plessite of this kind is attacked with more difficulty by acids than the 

 first named. In the plate lying before me troilite appears only in small, compact, round to elongated nodules, which 

 in a breadth of 4 mm. contain one to two daubreelite bands nearly 1 mm. broad and are not surrounded by swathing 

 kamacite. Schreibersite I nowhere detected. 



As stated, the meteorite is chiefly in the National Museum of Mexico. Ward, however, 

 reports 16,380 grams in the Ward-Coonley collection. 



BIBLIOGRAPHY. 



1. 1804: Del Rio. Tablas Mineralogicas, p. 57. 



2. 1840: El Mosaico Mexicano, Bd. 3, p. 219. 



3. 1863: Castillo and de la Loza. Descripciondelamasadehierrometeoricode Yanhiutlan. Boletin de la Sociedad 



de Geografia y Estadistica de la Republica Mexicana, 1st ser., vol. 10, pp. 661-672. 



4. 1865: Buchner. Zweiter Nachtrag. Ann. Phys. und Chem., Poggendorff, Bd. 124, p. 599 (Cholula). 



5. 1866: Bureart. Fundorte III (Abbildung der grossed Masse von Misteca, damals noch 421 kgr. schwer). Neues 



Jahrb., 1866, p. 402-408. 



6. 1869: Rammelsberq. Ueber zwei Meteoreisen aus Mexico. Zeitschr. deutsch. geol. Gesellsch., Bd. 21, p. 83. 



7. 1870: Burkart. Fundorte IV. Neues Jahrb. Min., 1870, pp. 688-689, and 692. 



8. 1890: Fletcher. Mexican Meteorites, Mineral. Mag., vol. 9, pp. 96, 99, 102, 104, and 171-173. 



9. 1892: Eastman. The Mexican Meteorites. Bull. Philos. Soc. Washington, vol. 12, p. 47. 



10. 1895: Brezina. Wiener Sammlung, pp. 268 and 275-276. 



11. 1905: Cohen. Meteoritenkunde, Heft 3, pp. 316-320. 



YORK. 



York County, Nebraska. 



Latitude 40° 45' N., longitude 97° 30' W. 



Iron. Medium octahedrite (Om) of Brezina. 



Found 1878; described 1898. 



Weight, 835.2 grams (1.8 lbs.). 



This meteorite was described by Barbour * as having been plowed up at the localityabove 

 mentioned in 187S. 



It is an iron showing Widmannstatten figures simply on burnishing and also upon etching. Its shape is discoidal 

 with large shallow pits. 



Analysis by Kunz 2 is as follows : 



Fe Ni Co 



87.96 7.38 0.74 =96.08 

 716°— 15 32 



