ON THE FAYETTE COUNTY, TEXAS, METEORITE FINDSOF 1878 AND 1900 AND THE PEOBABILITY OF THEIRREPRESENTING TWO DISTINCT FALLS.
By George P. Merrill,Head Curator, Department 0/ Geology, United States National Museum.
Under date of February 10, 1900, Prof. O. C. Charlton, then ofBaylor University, Waco, Texas, sent me two chips of a stony meteor-ite, concerning the exact nature of which he was in doubt, but whichwere brought to him by a Mr. C. L. Melcher, of Swiss Alp, FayetteCounty, in that State. Subsequent correspondence developed thefact that three stones had been found by Mr. Melcher, weighing,respectively, 16 pounds 9| ounces, 12 pounds 3^ ounces, and 2 pounds12 ounces. The meteoric nature of the material was easily estab-lislied, and from the locality where found, color, general texture, andother features of the stones, which were badly oxidized exteriorly, itwas assumed by me, as well as by others, that they were a part ofthe Fayette County (Bluff) stone found in 1878 and described byWhitfield and Merrill in the x\merican Journal of Science forAugust, 1888. The largest, nearly complete individual of this (1900)find passed immediately into the hands of H. A. Ward and is the8,619-gram mass figured on plate 64 of Farrington's catalogue of1916. A 3,136-gram piece, approximately one-half of the 12-poundindividual, is in the collection of the United States National Museum,and the remainder is or was in the cabinet of the university at Waco.As stated above, the identity of the find of 1900 with that of 1878was unquestioned at the time, and has apparently remained so untilthe present day. I, at least, had no occasion to doubt until a shorttime ago when examining a number of thin sections in connectionwith the occurrence of the problematic phosphate, concerning whichI have prepared sundry papers.^ That the two finds are not identicalbut must be regarded as two distinct falls will, I think, be apparentfrom the descriptions below.
* See On the Calcium Phosphate in Meteoric Stones, Amer. Journ. Sci., vol. 43, 1917,pp. 322-324.Proceedings U. S. National Museum, Vol. 54?No. 2248. 557
558 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 54.Concerning the stone of 1878, little more need be added to whatis given in the paper referred to above. A broken surface showsa dense, dark-brown stone, very indistinctly chondritic and withnone of the mineral constituents determinable by the unaided eye.A freshly polished surface is of a greenish-gray cast and showsabundant flecks of metal, but the chondritic structure still remainsobscure (see fig. 1, pi. 86). On going over the sections a secondlime I find the colorless interstitial mineral full of gas cavities,referred to in my paper of 1888, and concerning the nature of whichI was then in doubt, to be a calcium phos-phate occurring in the characteristic, irregu-lar fornis (see text-fig. 1). It differs some-what from other occurrences which I havedescribed in that it shows a somewhat higherrelief in the section and is rendered actuallyclouded by the abundance of empty, irregularcavities. Its phosphatic nature has been de-^S '^sTnJ.TZ:^Z^ termined beyond doubt by microchemical tests.Bluff, Fayette County, The first chips forwarded of the stone foundMETEORITE. ACTUAL SIZE . ^ r\r\r\ T IS> 1 1 j. Tj.j.1 ?about 1.5 MM. IN GREATEST m 1900 diiiered but little m macroscopic ap-DiAMETER. pcaraucc from the above, being dark brown-ish in color with no distinctive structural features, though in thinsection the chondritic structure is much more pronounced (see fig.2, pi. 86). The most striking difference lies in the physical condi-tion of the two prevailing silicates, the olivine and enstatite. Inthe stone of 1878 they are so filled with dust-like particles as to bedull and cloudy, while in that of 1900 they are clear and pellucid.The difference may be compared with that so frequently foundbetween the feldspars of some of our older granites and those of themore recent effusive rocks. Further, the ground of the stone of1900 is doubtfully crystalline. Indeed, I am disposed to considerit fragmental, and to class the stone, following Brezina, as a veinedspherulitic chondrite (Cca). An equally distinctive feature, how-ever, lies in the fact that in the slides of the 1900 stone I find numer-ous chondrules composed wholly of the polysynthetically twinnedpyroxene, none of which appear in any of the slides examined ofthe 1878 find. The calcium phosphate occurs here also, but in clear,limpid forms lacking the cavities so conspicuous in the .other. Bothstones are veined, though in the find of 1900 the vein filling seemsless dense and the included silicate fragments more angular andotherwise less altered.An interesting feature brought out by a cross section and shownin plate 87 is the peculiarly pitted character of the interior of the
NO. 2248. FAYETTE COUNTY, TEXAS, METEORITE?MERRILL. 559mass in contrast with the more compact exterior portion and that bor-dering on the fracture lines or veinlets which traverse it in variousdirections. All around the margin, for a width varying from 1 to 2centimeters, is a zone of oxidation projecting irregularly inward, andwithin which the stone is firm and compact, acquiring a smooth,Justrous surface, and with abundant small, metallic points, mainlyof troilite. Each of the veinlets has a similar border varying inwidth up to 10 millimeters. The areas between the boundary, zoneand the emargined veins are relatively poor in metallic constituents,and filled with numerous very irregular, minute cavities. The causeof these pittings can not be satisfactorily explained. They are toonumerous and too large to have been occupied by metal, in which,in fact, the stone is poor, and indeed it would seem impossible thatthe metal could have been removed without the sulphide also suffer-ing to a greater or less extent. Neither can they be due to the partialremoval of the sulphide, since this mineral remains fresh and un-altered in the outer zones and those bordering the veins, where itwould most likely be attacked. Except on the immediate weatheredsurface this constituent remains quite untouched. The thought sug-gests itself that the cavities may have been filled originally bylawrencite, but the presence of so large a quantity of this mineralmust certainly have resulted in the complete destruction of the stonewhen exposed to a terrestrial atmosphere. The veinlets, it may besaid, are filled by disconnected stringers of metal, sulphide, carbo-naceous matter, and secondary iron oxide. In the slice figured thereis relatively a large amount of troilite as compared with nickel iron,while in the Bluff stone of 1878 the reverse is true. In a section froma chip of the mass in the Field Museum, which Doctor Farringtonhas kindly furnished, this does not hold true, however.It remains to be noted that the 3,136-gram individual of the 1900stone is more deeply oxidized than that of 1878, which may perhapsmean that it has been longer exposed to terrestrial weathering andinferentially belong to an earlier fall.The relative positions of the various finds of 1878 and 1900 areshown in the accompanying chart (p. 560) prepared by Mr. Melcherin 1900, but which reached my hands from Professor Charlton onlya few days ago. Nos. 1, 2, and 3 on the Knape, Strobel, and Sanderstract represent the localities of the finds of 1900. No. 4 is the 1878stone brought by Hensolt to New York, sold to Ward, and describedby Wliitfield and myself in 1888 under the name of Fayette (after-wards changed to Bluff) County. It will be noted it is somewhat outof line with the other three. The distance between Nos. 1 and 3 onMr. Melcher's drawings is given as about 2^ miles, and 1 mile from2 to 4.
560 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. 5 4.
RAINOSEK
TRACT
FIND
OF1878
NO. 2248. FAYETTE COUNTY, TEXAS, METEORITE?MERRILL. 561The differences between the finds of 1878 and 1900, as I havepointed them out, are in my opinion amply sufficient to warrant theirbeing considered distinct falls. The question of what this 1900 fiindshall be called is a troublesome one. The name La Grange wouldbe appropriate, but that it has been given to an iron from OldhamCounty, Kentucky. That of Swiss Alp, Mr. Melcher's post-officeaddress, is unfortunately geographically misleading. It is sug-gested, therefore, that the stone of 1900 be known as the Cedar,Fayette County stone. Cedar being the name of a small village alittle to the southwest of Bluff.3343?19?Proc.N.M.vol.54 37

U. S. NATIONAL MUSEUM PROCEEDINGS. VOL. 54 PL.
The Fayette County, Texas, MeteoriteFor Description of plate see page 558

U. S. NATIONAL MUSEUM PROCEEDINGS, VOL. 54 PL. 87
Polished Slice of the Cedar, Fayette County, Texas, MeteoricStone, about two-thirds natural sizeThe polished surface shows a dark, compact margin thickly studded with particles of troi-lite and some nickel iron (white m the figure). The veins, or properly the cracks, cuttingacross the surface are emargined by like narrow, compact borders carrying the same con-stituents. Tht intermediate gray portions are full of pits or cavities, also showing inwhite, which at first sight seemingly result from the removal of the metal and mefallicsulphide. (Seep. 558.) For explanation of plate see page 558