502 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. XIII. 



I had cut in 5 parts by 3 incisions in different directions, and etched in different degrees, yielded figures which I 

 regard as an example of well-developed kamacite formed in both directions indicated (either crumpled or straight). 

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 Zacatecas belongs with meteoric iron of the Triassic system, in which no combs have been observed. 

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 Zacatecas exhibits an especially well marked case of the inclusion of iron sulphide in an envelope of puffy kamacite, 

 surrounded by the usual trias of which the meteorite is mainly composed. Zacatecas has no regular Widmannstatten 

 figures, but a crystalline structure which approaches very near to it. 



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 Zacatecas contains many scattered particles with a whitish luster which often run into short rows. 

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 In Zacatecas the magnetic pyrites are entirely enclosed with Glanzeisen (Lamprite). 

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 The metallic luster shows very distinctly in Zacatecas. 



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 In my specimen of Zacatecas iron sulphide occurs in small nodules of from C to 3 lines in diameter with a bronze- 

 colored appearance resembling gun metal, sometimes polished and sometimes with dull unburniBhed appearance. 

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 The iron sulphide in Zacatecas assumes the vermiform shape. 



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 The cones (of schreibersite) or the tubular molds of the same occur in Zacatecas upon a specimen in the Berlin 

 University collection, but in comparatively smaller forms about the thickness of a pen quill. Zacatecas contains, 

 also, larger and smaller fragments of roundish, bronze-colored iron sulphide embedded in it. 



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 Zacatecas affords a fine example of the occurence of iron glass. In the middle of a fragment of this meteorite 

 there appears upon the weakly etched section surface a black, brightly glistening circle, somewhat elongated, which 

 consists of iron glass. It has a narrow canal from below outward, through which it filled from the outside. 



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 A specimen of Zacatecas in my collection shows more or less pronounced fissures where the iron is sundered. 



Burkart u discussed the locality from whence Zacatecas may have come, as follows : 



Unfortunately the locality (hacienda) at which Cavaroz made a long halt, before his arrival at Zacatecas, is not 

 indicated by name, nor is it even mentioned from which side of Zacatecas it is reached. Cavaroz mentions the occur- 

 rence of fossil remains of mammals not far from Cuquio. This is a little town (Lat. 21° 40' N.) 15 leagues northeast 

 from Guadalajara, in the State of Jalisco, in which such remains are found at different points. May we conclude from 

 this that it is reached from Cuquio to the latter (hacienda) and then from this hacienda farther northward toward Zaca- 

 tecas, or is it reached, with the French troops from Mexico, by another road to Zacatecas? In both cases, the hacienda 

 in question would be south of Zacatecas. Yet this determines nothing concerning the place of discovery of the 

 meteorite in question, since there are many fine haciendas in the extensive environs of Zacatecas. The iron is said 

 to have been brought a long time ago from Zacatecas to its new locality; but it is not mentioned where it was found 

 there, and still Cavaroz concludes from the character of the ground in the locality that it was meteoric (and not ter- 

 restrial) iron. 



In Zacatecas, where I lived for a long time and which I frequently visited, I heard nothing about any second 

 piece of meteoric iron having been in existence there at an earlier date. According to very uncertain data, the speci- 

 men which belonged there is said to have come thither from the north, then to have lain at the neighboring mine — 

 Guebradilla — and from thence to have been brought into the city. I had received no information from England in 

 regard to the examination there of any meteoric iron from a hacienda in the neighborhood of Zacatecas. Consequently, 

 Doctor Cavaroz himself, or else some one of his companions of the French army in Mexico, may be able to give more 

 exact information concerning the locality in question, than this Daubree, who has obtained a great reputation in this 

 field, because of his investigation of different meteorites, may be in a position to obtain. 



Brezina, 15 in 1885, placed Zacatecas in a group by itself as a brecciated octahedrite. The 

 characteristics of this group he defined as follows : 



Walnut-sized parts, each showing octahedral structure, with numerous large troilite nodules 2 to 3 mm. pene- 

 trated by small, often to large, troilite plates. 



Castillo 16 states that the Zacatecas meteorite — 



was originally found in the Rue Royale, of the city of Zacatecas, and was moved to the hacienda of Cieneguillas, the 

 property of the Gordoa family. It has the form of a parallelopipedon 1.06 m. in length, 0.5 m. in width, and 0.25 m. 

 in height or thickness. Its volume is 132 cu. dm., and its density 7.7, giving a weight of 1,000 kg. 



Fletcher 17 remarks that . the piece of Zacatecas referred to by Cavaroz 12 as having been 

 taken to England for study is probably the one weighing 20 pounds, which was described and 

 analyzed by Miiller in 1859. 



