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The Fisher, Polk County, Minnesota, MeteoriteShow simple item record

dc.creatorMerrill, George P. (George Perkins), 1854-1929
dc.date.accessioned2024-02-12T18:10:33Z
dc.date.available2024-02-12T18:10:33Z
dc.date.issued1915-05-03
dc.identifier.urihttps://repository.tcu.edu/handle/116099117/63104
dc.descriptionPages 503-506 with plate 29 featuring details about the Fisher Minnesota meteorite.
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, Fisher, MN folder
dc.subjectMeteorite
dc.subjectFisher meteorite
dc.subjectFisher (Minn.)
dc.subjectMetallography
dc.subjectCharlton, O. C.
dc.subjectMerrill, George P.
dc.titleThe Fisher, Polk County, Minnesota, Meteorite
dc.typeDocument
dc.description.transcriptionTHE FISHER, POLK COUNTY, MINNESOTA, METEORITE BY GEORGE P. MERRILL Head Curator, Department of Geology, United States National Museum No. 2084.-From the Proceedings of the United States National Museum, Vol. 48, pages 503-506, with Plate 29 Published May 3, 1915 Washington Government Printing Office 1915 THE FISHER, POLK COUNTY, MINNESOTA, METEORITE.By GEORGE P. MERRILL, Head Curator, Department of Geology, United States National Museum. In the American Geologist for December, 1894, brief mention is made of the finding near Fisher, Polk County, Minnesota, of a meteoric stone weighing 91 pounds. This, the first found within the State limits, was assumed to be a representative of a reported fall which took place on the 9th of the preceding April. In a subsequent number of the Geologist, Prof. N. H. Winchell began a petrographic description of the stone, which was continued over into volume 20, 1897, but not completed, nor was a satisfactory chemical analysis made.' In view of these facts and the subsequent finding of more material, a complete reviewal of the matter seems desirable. According to Professor Winchell there had been found at the time he wrote but two stones, one, the 91-pound mass mentioned above, and one, weight unknown, "but larger," which was broken up and largely lost, though several pieces passed into the possession of Dr. George F. Kunz. Later three other individuals were found, one of which, a beautifully perfect stone weighing 1,312 grams, came into the possession of the United States National Museum. The following information concerning the fall and finding of these pieces was furnished the writer by Mr. C. J. Sweet: On that date [that is, April 9, 1894] persons in the neighborhood of here [Fisher] heard a loud explosion followed by a hissing noise as of steam escaping from high pressure, and then a thud as if something had struck the earth very solidly. Of course nothing was known of the cause of the disturbance at this time, but in the summer following a black stone was found which proved to be a meteorite of 94 pounds weight. This piece was sold to the Minnesota State University, the authorities there claiming it the first which was ever found in this State. The next summer (1895) two small pieces of the same meteorite were found by me and sold to a firm in New York. This summer (1898) I found another piece when breaking up a new field. This piece weighs slightly less than 3 pounds. In addition to information furnished as above, I am informed by Dr. E. O. Hovey that there is in the American Museum of Natural History, New York, "a beautiful specimen of Fisher, Polk County, Minnesota, aerolite approximately 16.4 cm. by 10.6 cm. by 8.1 cm., weighing 1,765 grams, with crust well preserved. One curved surface shows the original crust and there are about six fractured surfaces showing a secondary, tertiary, or perhaps quarternary crust with pittings and flowage lines." Doctor Hovey further states that a second mass from the same source, weighing 1,850 grams, was sent by the American Museum to Doctor Gottsche of Hamburg. These two stones were originally in the possession of Dr. G. F. Kunz and are beyond doubt the two found in 1895 as mentioned by Mr. Sweet above. A third fragment, weighing 28 grams, he also records as having passed in 1918 into the hands of the dealer, W. M. Foote, and 22 grams are listed by Doctor Berwerth in his collections in the Vienna Museum. Dr. O. C. Farrington reports, in answer to inquiry, that the Field Museum collections include three fragments weighing, respectively, 133, 185, and 277 grams. Two of these are doubtless from the Ward-Coonley collection mentioned in the catalogue of 1904. It would seem practically certain that all of these fragments were from the larger mass mentioned by Winchell, the principal portion of which is lost. The distribution and weights as known to-day are then as follows: University of Minnesota, Minneapolis 4,340 grams, United States National Museum, Washington 1,300 grams American Museum, New York 1,765 grams Natural History Museum, Hamburg 1,850 grams Field Museum, Chicago 595 grams Vienna Museum, Austria 22 grams W. M. Foote, Philadelphia 28 grams Total 9,900 gram Through the courtesy of Prof. W. HI. Emmons of the University of Minnesota, the writer has had the opportunity of examining the stone in the possession of that institution and was also granted permission to cut from it a sufficient amount to guarantee its identity with that in the Museum collections and to supplement sufficiently that cut from our own specimen to insure a satisfactory chemical analysis. The general appearance of the stone on a broken or polished surface is closely similar to that of Forest City, Iowa, and still more to that of Coon Butte, Arizona.' The stone is of a compact texture, sufficiently firm to admit of a polish, of a light gray color, and is thickly spotted with metallic points in sizes up to 3 mm. in diameter with numerous small, distinct, light gray chondrules and more rarely larger (2 mm.) white forms. Each specimen examined shows one curved, crusted area, with few distinct pittings, evidently a portion of the surface once continuous over the entire mass (A in plate). The remaining surfaces, which are plainly due to the fracturing of the stone in the lower atmosphere, are characterized by shallow pits. All are coated with a black, lustreless, somewhat rough coating caused by the unequal fusibility of the various constituents. This is plainly shown in the half tone reproductions from the photographs. Three crusts are recognizable (1) that first formed (A in plate), (2) a thinner crust covering the earliest fractures, and (3) a very thin crust covering limited areas of secondary fracture. I find no certain evidence of a quarternary coating, as mentioned by Doctor Hovey, on the specimen in the American Museum. Under the microscope the stone is found to consist of a confused aggregate of irregular crystalline granules of olivine and pyroxene interspersed with numerous imperfectly outlined chondrules, consisting also of olivine and pyroxene, throughout which are occasional interstitial areas occupied by a colorless, pellucid, faintly doubly refracting or quite isotropic material, referred to maskelynite. Small areas of nickel and iron sulphide complete the list of determinable minerals. The chondrules are sometimes wholly of pyroxene, either in stout irregular crystals or in fan-shaped and dendritic forms, and sometimes of olivine, the latter also in barred and radiating forms. Both types of chondrules contain numerous inclosures [enclosures] of the colorless mineral mentioned above. No truly porphyritic forms were noted. The pyroxenes all give parallel extinctions and are devoid of twin structure. The colorless interstitial material seems sometimes quite isotropic or again faintly doubly refracting, with an index of a refraction of but 1.51 as determined by the immersion method.' A chemical analysis on materials selected to insure its representative character, yielded Dr. J. E. Whitfield results as below: The chromium present is tabulated as chromite, as it occurs as such in the stone. No barium, strontium, zirconium or potassium could be detected by analysis. The metallic portion freed from the last trace of siliceous matter contained: On recalculating, these figures give the balk or mass composition of the stone as follows: With traces of sulphur and soda but none of barium, strontium, zirconium, or potassium. Specific gravity, 3.37. Following Bre zina's classification the stone would be placed in the group of intermediate chondrites Ci, or perhaps Cia, as one cut surface shows a small threadlike black vein. EXPLANATION OF PLATE 29. Fig. 1. The 1,300-gram piece in the United States National Museum, Cat. No. 212. 2. The 4,340-gram piece in the museum of the University of Minnesota. In both figures the areas marked "A" show the earliest formed crust, the other pitted surfaces, the secondary and tertiary crusts. The Fisher, Polk County, Meteorite. For explanation of plate see page 506.


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  • Records of the Monnig Meteorite Gallery [2678]
    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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