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The Fayette County, Texas, MeteoriteShow simple item record

dc.creatorWhitfield, J. E.
dc.creatorMerrill, George P. (George Perkins), 1854-1929
dc.date.accessioned2024-02-12T18:10:15Z
dc.date.available2024-02-12T18:10:15Z
dc.date.issuedn.d.
dc.identifier.urihttps://repository.tcu.edu/handle/116099117/63083
dc.descriptionAn article exploring the history, characteristics, and mineral composition of the Fayette County, Texas meteorites.
dc.relationOscar Monnig Papers (MS 124)
dc.rightsPrior written permission from TCU Special Collections required to use any document or photograph.
dc.sourceSeries III, Box 06, Fayette Co., Texas literature folder
dc.subjectMeteorite
dc.subjectFayette County meteorite
dc.subjectFayette County (Tex.)
dc.subjectBluff meteorites
dc.subjectCedar meteorite
dc.subjectMerrill, George P.
dc.titleThe Fayette County, Texas, Meteorite
dc.typeArticle
dc.description.transcriptionThe following are the figures obtained by analysis on material that weighed a little less than 04 grams: The same difficulty, with regard to water in the mineral, exists here as in the analysis of the mass. From the figures it appears that the portion soluble in hydrochloric acid is essentially olivine in composition, while the insoluble is evidently a mixture of the same insoluble constituents as the mass of the meteorite. The filling material of the vein is, to the unaided eve, quite black and without luster; under the microscope it is seen to penetrate very irregularly and by innumerable minute vein-like ramifications into the stony mass on either side and to carry numerous enclosures of a colorless mineral substance and blebs of metallic iron and pyrrhotite. The exact nature of the colorless enclosures can. not be ascertained. On treating an uncovered slide with hydrochloric acid a part of these were dissolved, others were enacted upon. Under the microscope they are full of irregular rifts and fracture lines but show no true cleavages. Some of them are in the form of single individuals, others have the structure of fragments of polysomatic chondri Nearly all contain included black amorphous material and many show distinctly included specks, giving, the silvery white and brassy yellow reflections of the metallic iron and pyrrhotite. In many cases they are not separated from the black vein material by sharp lines but seem.to pass into it by gradations. Between crossed nicols many of them act like a gum, others remain always light, recalling the well known crypto-crystalline structure of chalcedony and still show, here and there, occasional small areas giving the characteristic polarization colors of olivine and enstatite. On examining the walls of the vein, areas were observed where the gray and yellowish enstatites and olivines retained their normal properties at the distance of one or two millimeters, but at contact with the black vein matter were reduced to the colorless non-polarizing condition of the enclosures. The black matter of the vein when viewed in strong reflected light shows a dull bronze luster, less brilliant than that of the pyrrhotite particles which it encloses. The thinnest portions of the slide when examined with a power of 175 diameters show a brownish amorphous base through which are scattered abundant irregular dust-like particles and flecks of a perfectly black opaque material, the mature of which it is impossible to ascertain by the microscope alone. The structure of the vein is shown in figure 3 in which the finely dotted portions represent the black amorphous vein matter with bronzy luster, the entirely black area, the blebs of metal and pyrrhotite, and the irregularly rounded, clear or partly clouded area, the colorless silicates. From the study of these veins as above described, we are inclined to consider the colorless particles as olivine and enstatite residuals which have been deprived of their normal optical proper. ties by the forces active in forming the vein. What the exact character of the black and amorphous material may be, still remains a matter of conjecture. It is unacted upon by acids and when tested with a needle point it breaks up readily into earthy fragments which are not attracted by the magnet. Mr. Howell informs us that the stone in his possession shows three of these veins, the largest exposure of any one on a broken surface being about four inches. The width and general character of all, he states, appears to be uniform throughout, though this can be ascertained definitely only by breaking the stone. Owing to the small amount of vein material which was available for chemical analysis and the impossibility of separating it completely from the enclosing rock, the results obtained can be regarded only as suggestive. The main points brought out can be best shown by reproducing here a comparison of the results: These differences are too slight to be considered of great value until found to be constant by further investigation. It iss to be hoped that the ultimate possessor of the stone will regard a knowledge of its true character as of first importance and will not hesitate to sacrifice any necessary amount for the purpose of an exhaustive examination by the most advanced methods. Our most sincere thanks are due Mr. Hensoldt for kindly furnishing us with the information regarding the discovery of the meteorite.


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  • Records of the Monnig Meteorite Gallery [2825]
    The files are arranged alphabetically, usually according to the location of discovery of the meteorite. The files contain correspondence and research material on the meteorites in the collection.

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