SCIENTIFIC NEWS. 



[July 6, 1888. 



DIAMONDS FROM THE HEAVENS. 



BETWEEN September 10 and 22, 1886, after the usual 

 phenomena which accompany the arrival of meteo- 

 rites, there fell three stones near the village of Nowo-Urei, 

 in the government of Penza, in South-Eastern Russia. 

 One of them was lost in a marsh ; another was found by 

 a peasant who, induced by a curious superstition, ate 

 this wonderful substance arriving from heaven ; the 

 third was offered to the Mineralogical Cabinet of the In- 

 stitute of Forests at St. Petersburg, where it has been 

 carefully examined both mineralogically and chemic- 

 ally. 



According to an account furnished to the Academy of 

 Science by MM. Jerofeieff and Latchinoff, this stone, 

 before being cut, weighed above four pounds. A 

 part of its surface is remarkable for the deep piezo- 

 glypts which the mechanical action of the air has dug 

 into it during its rapid flight. This surface is free from 

 incrustation, as has been already observed in the case 

 of several black meteorites, such as those of Tadjera. 

 The fracture is almost black, but marked over with 

 small particles, some of them white and others metallic. 

 It is irregular and rough, but it does not present, as we 

 find in many cases, a globular structure. Its specific 

 gravity is 3'46. 



By analysis it has been found that the meteorite of 

 Nowo-Urei consists of fragments of peridote and pyro- 

 xene, between which is interposed a mixture of nickeli- 

 ferous native iron and carbonaceous matter. There has 

 also been recognised the presence of pyrrhotine and of 

 chrome iron. 



It will be understood that this is a mineralogical, not 

 a chemical analysis, the ingredients mentioned being 

 themselves complex. 



The carbonaceous matter amounted to 23 per cent, of 

 the entire stone. By successive treatment with aqua 

 regia, hydrofluoric acid, and bisulphate of potash and by 

 Brodie's process as adopted by Berthelot, it has been 

 ascertained that the carbonaceous matter is a mixture of 

 amorphous carbon and of diamond, perhaps of the 

 variety known as carbonado, both in the state of micro- 

 scopic grains. 



The diamond has been recognised as such by its 

 hardness, which is such as to eat rapidly into a polished 

 surface of corundum which was rendered dull, and 

 covered with fine scratches. The meaning of this test 

 will be understood if we remember that corundum is, 

 next to the diamond, the hardest substance known. 



The mean specific gravity — of course, of the carbo- 

 naceous part — is close upon that of the diamond, 3-5. 



When heated in a current of oxygen, the substance 

 burnt yielding carbonic acid, and indicating a composi- 

 tion of 95'4o per cent, of carbon and 3-23 of ash. 



In fine, the Russian mineralogists are led to conclude 

 that the meteorite in question contains, in addition to 

 i -26 per cent, of amorphous carbon, diamond in the pro- 

 portion of 1 per cent., but in very fine dust. The authors 

 remark that, as the meteorite weighed 1,762 grammes, it 

 contained 17-62 grammes of diamond, or 85-43 carats. 



This discovery of diamond in a meteorite is not as 

 unprecedented as it might seem at first sight. 



The meteoric iron or holosiderite of Arva in Hungary 

 is not only remarkable for its large proportion of phos- 

 phorus in the state of Schreibersite, a double phosphuret 

 of iron and nickel, but also contains graphite in a cubic 

 form. Hence Hardinger was of opinion that this crystal 



might be derived by pseudomorphosis, from iron 

 pyrites, for which graphite had been substituted. But 

 Gustav Rose remarked that these crystals present rather 

 the form of the diamond, and that iron pyrites have never 

 yet been recognised in meteoric stones. 



M. JDaubree made the following remarks in addition : — 

 In Brazil, the diamond in the sands in which it is sought 

 for is accompanied by rutile, anatase, brookite, oligiste, 

 tourmaline — that is to say an assemblage of fluoric and 

 boric minerals, to the origin of which the diamond in this 

 region seems to attach itself. In New South Wales, as 

 Professor Liversidge has shown, the diamond is attended 

 by the same minerals. Besides quartz, tourmaline is 

 frequent along with brookite, ilmenite, topaz, corundum, 

 and cassiterite (tin-stone), a mineral for which the inter- 

 vention of the same fluoric or chloric agents is generally 

 admitted. 



In the important deposits of South Africa the diamond 

 occurs in a very different manner, being associated with 

 a serpentine brecchia in which the crystals are some- 

 times encased. But nothing shows that it has remained 

 in its original matrix. It appears rather to have been 

 torn away from the depths, and to have risen to the 

 surface. 



In the gangue of cosmic origin, which the meteorite of 

 Nowo-Urei supplies, the diamond occurs in a manner 

 different from the deposits on our globe. Its associa- 

 tion with amorphous carbon is doubtless not accidental. 

 Either the diamond, so refractory to the efforts of 

 mineralogists for its artificial production, has separated 

 itself by crystallisation from a carbonaceous medium, or, 

 what is more probable, the diamond merely represents 

 the residue of a partial transformation, which tends to 

 change it completely into the state of graphite. 



This last supposition seems particularly applicable to 

 graphite in diamond-like forms, like that occurring in the 

 meteoric iron of Arva. Seized and enclosed in a mass 

 of iron, the high initial temperature of which is attested 

 by the abundance of distinctly crystallised metallic 

 phosphurets, it must necessarily lose its original state, 

 and could not escape a change into the allotropic con- 

 dition of graphite, with which we are experimentally 

 familiar. 



In the cosmic rock of Nowo-Urei the preservation of 

 the diamond is surprising. It leads us to believe that 

 the temperature of this rock, since the time when the 

 diamond was developed, cannot have been very high, 

 probably not reaching the melting point of peridote and 

 pyroxene, in the midst of which it is found. Another 

 proof is that nickeliferous iron could remain in the 

 presence of free carbon without combining with it, as 

 would probably have been the case at a high tempera- 

 ture. 



Graphite abounds in meteorites, especially in Holosi- 

 derites, often isolated in nodules, as in the specimen 

 from Arva, but more often in cylindrical cases around 

 rods of pyrrhotine. 



The Relations of Astronomy and Astrology. — Pro- 

 fessor Newcome {Sidereal Messenger) remarks that as- 

 tronomy is often said to have been eagerly cultivated in 

 the past because it served as a starting-point for the 

 astrologers. But nothing in the writings of antiquity and 

 of the middle ages supports this opinion. On the contrary, 

 astrology must be regarded as an aberrant daughter of 

 astronomy. 



