Home › Meteorites, or Celestial Stones › Meteorites, or Celestial Stones: Koenig

Meteorites, or Celestial Stones: Koenig

Davison Whitfield Iron 91.65 91.46 Nickel 7.88 8.30 Cobalt .21 ? Phosphorus .09 ? 99.83 99.76 The famous Canon Diablo meteorite possesses a surpassing mineralogical interest. In 1891, at the Tenth International Geologic Congress, Washington, D. C., the mineralogist Koenig announced that he had discovered some microscopic diamonds in this meteorite, and later investigations by Prof. Henri Moissan confirmed this discovery and enlarged its scope. A mass of the iron weighing about 400 pounds was used by Professor Moissan; this was cut by means of a steel ribbon saw. As had been the case in Koenig's investigations, the saw soon encountered excessively hard portions that obstructed its operation, so that twenty days' labor was requisite to separate the iron into two parts, each with a section area of nearly 100 square inches. On close examination it became evident that the obstacles to the cutting consisted of round or elliptical nodules, of a dark gray to black hue, and enclosed in the bright iron. These nodules were mainly composed of troilite (iron protosulphide). After chemical treatment an insoluble residue remained, consisting of silica, amorphous carbon, graphite and diamond. Many of these very minute diamonds were black, but a few were transparent crystals, octahedrons with rounded edges. The presence of this diamond material in the interior of the iron mass of the meteorite indicates their formation from carbon by the combined agencies of high temperature and great pressure, as in the case of the artificial diamonds experimentally produced by Moissan in an iron mass first subjected to intense heat in the electric furnace and then rapidly contracted in volume by sudden chilling. The fervid imagination of early writers would certainly have attributed wonderful talismanic powers to stones like these, probably generated in some lost planet and reaching our earth through the wastes of celestial space, could they have been able to observe and distinguish them with the incomplete optical resources of their time.

The first announcement of the discovery of these diamonds from the Canon Diablo meteorite was made by Dr. A. E. Foote, and not long after Professor Koenig's determination of their character, the present writer suggested an experiment that would afford absolute proof that the material was really diamond. This was to charge a new skaif, or diamond-polishing wheel, with the supposed diamond dust obtained from the meteorite; should the material polish a diamond there could be no doubt as to its character. On September 11, 1893, this experiment was tried at the Mining Building of the World's Columbian Exposition. After the skaif had been charged with the residuum separated from the meteorite by Dr. O. W. Huntington, it was given a speed of 2500 revolutions to the minute, and in less than fifteen minutes a small flat surface had been ground down and polished on a cleavage-piece of rough diamond held against the wheel. The experiment was then repeated several times on other diamonds and always successfully. This showed conclusively that the residuum of the meteorite contained many minute diamond fragments. A most important group of meteorites were found in 1886 in Brenham township, Kiowa County, Kansas, by some of the farmers of this district in the course of their farming operations. Entirely unaware of their scientific value, the finders used these objects to weight down haystacks, or for similar uses to which they would put small boulders. In all some twenty of these specimens have been recovered, varying in weight all the way from 466 pounds down to a single ounce. Most of them were taken from an area of about sixty acres, although some were scattered over a wider tract. The largest piece of the group, that on which the farmers had bestowed the fanciful name of the "moon meteorite," had lain only three inches beneath the surface of the ground and broke a ploughshare when it was first struck; none of the masses appear to have been buried deeper down than from five to six inches. The largest mass measures twenty-four inches across the widest part and fourteen and a half at the thickest part. These Kiowa meteorites are in a sense gem-meteorites, for a number of beautiful and brilliant olivine crystals occur in them; many are in two distinct zones, the inner one being a bright transparent yellow, while the outer one is of a dark-brown iron olivine, in reality a mixture of troilite and olivine. The character and composition of the worked iron of meteoric origin found in some of the Turner group of Indian mounds, in the Little Miami Valley, Ohio, indicate that the latter may perhaps be brought into connection with this group of meteorites. For here, as in the Frozen North among the Esquimo, and in a number of other cases, the iron available for primitive man was mainly that of meteorite origin.

In view of the relatively small number of meteorites that have fallen in historical times, and of the small part of the earth's surface actually occupied by human settlements, we need scarcely be surprised at the statement that there is but one credibly recorded instance of the killing of a human being by a meteorite. This unique disaster is said to have happened at Mhow in India, and fragments of the meteorite which fell then are to be seen in museum collections. The great weight of some meteorites would have rendered them very destructive had they not fallen in the open country; the heaviest single mass actually known to have fallen, came to the ground at Knyahinya, Hungary, in 1866, and weighed 547 pounds; it buried itself 11 feet in the ground. Of course much heavier aerolites and siderites, satisfactorily recognizable as such, have been found, the heaviest being perhaps that at Bacubrit, Mexico, 13 feet in length with a width of 6 feet and a thickness of 5 feet; the weight of this mass is estimated to be some 50 tons. Of meteorites which have fallen in more or less close proximity to human beings, may be noted one at Tourinnes-la-Grosse, which broke the street pavement; another at Angers, which fell into a garden, near to where a lady was standing; and still another at Brunau, which passed through a cottage roof.