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DIAMOND IN INDIA

India has now lost all its former fame as a country rich in diamonds; the most productive mines have long ago been exhausted, and only the poorer deposits still remain. During the devastating wars and native struggles for supremacy, many only partially exhausted mines were abandoned and their very sites forgotten, while from the same cause the demand for diamonds fell off. Moreover, the oppressive and unreasonable tribute demanded by native rulers in former times, so crippled the industry that many diamond seekers forsook the mines for more lucrative employments, to return perhaps under more favorable conditions.

The chief blow, however, to the diamond mining industry of India was the discovery of the precious stone in Brazil, a country from which diamonds have been sent to the market since 1728. There could be no competition between these new rich deposits and the Indian mines, whose age can be counted in centuries or even tens of centuries. More recently; the rich yields of the South African diamond-fields have made a profitable mining of the Indian deposits still more impossible. Since in India no new and rich deposits have been discovered to take the place of the old, worked out mines, as has been the case in Brazil, the time cannot be far distant when India must be excluded from the list of diamond-producing countries. It has been thought that the diamond-mining industry of India might revive were mining operations to be in the hands of Europeans instead of in those of the natives. Several attempts have been made in this direction, but up to the present have been attended with but little success. Though the economic, social, and legislative conditions even here are none too favorable for the undertaking and carrying out of systematic work, they are less adverse than in districts under the sway of native rulers, such, for example, as those in which the Golconda and the Panna groups of mines were situated, and which were very inaccessible to Europeans. As the geological structure of the country is worked out and becomes better known, it is possible that new occurrences of the diamantiferous beds may be discovered, though it must be said that at present there is no immediate prospect of such discoveries.

The insignificance of the annual output of Indian diamond-mines has already been commented upon; the proportion of these stones which reaches the European markets is still more insignificant; indeed, it is doubtful whether any appreciable number leave the country at all. This state of affair finds it's parallel in the times preceding the eleventh century; now, just as then, the stones are kept in the country to satisfy the passion for gems of the great Indian princes and magnates. Another inducement to dealers to keep the stones in the country is the fact that they will frequently make a higher price there than in the European markets, where they must undergo comparison with the treasures of the whole world and where the price is regulated by the inexorable laws of supply and demand. So brisk is the demand for diamonds in the Indian markets that the native supply is barely sufficient, and many foreign stones are imported, especially from the Cape.
There are not many detailed statements of the mineralogical characters of Indian diamonds; a few, however, have been collected and are given below.

It is often stated that the usual crystalline form of Indian diamonds is that of the octahedron, while that of Brazilian crystals is more often the rhombic dodecahedron, the two being often distinguished as the Indian and Brazilian types respectively. This view, however, is not in complete agreement with some recent scientific investigations of stones, which are certainly known to have been found in India. It appears on the contrary that the octahedral form is seldom seen in India, the more characteristic forms being the tetrakis-hexahedron and the hexakis-octahedron. Of fourteen crystals of diamond in the Museum of the Geological Survey of India at Calcutta, which were examined by Mr. F. R. Mallet, nine show a tetrakis-hexahedron alone, two show this form with subordinate faces of the octahedron, two are octahedra in combination with a tetrakis-hexahedron, and one is an octahedron in combination with the rhombic dodecahedron. A tetrakis-hexahedral form is thus present in thirteen of these fourteen crystals and on eleven of them it occurs singly or predominates over other forms; on the other hand, the octahedron is present on five crystals only; and on only three of these does it predominate. Of the fourteen crystals examined, five were from the Karnul district (four tetrakis-hexahedra and one octahedron with tetrakis-hexahedron), one from Sambalpur (tetrakis-hexahedron with octahedron), four from Panna (much distorted tetrakis-hexahedra), the remaining four being said to have come from Simla.

Also of thirty-one Indian diamonds in the mineralogical collection at Dresden only six were octahedra, while octahedral faces are present on only two or three more; the majority show the form of a hexakis-octahedron, and a few also that of the rhombic dodecahedron. The crystalline form of the stones found in different districts, when known, has been mentioned above under the special description of each district. That large diamonds in considerable numbers were formerly found in India has already been stated; a detailed description of the largest and most beautiful is given in a separate pages devoted to the consideration of famous diamonds. The stones found at the present day are usually of small size, so that in this respect also the finds of the present day do not compare favorably with those of earlier times; large stones are, however, occasionally met with, as is shown, for example, by the discovery of a stone weighing 67 3/8 carats at Wajra Karur in 1881.

With respect to the quality of Indian diamonds not many detailed accounts are available. Though reports dealing with single mines may mention the existence of stones of poor quality, yet, as a general rule, Indian stones rank high in the possession of the most desirable qualities. An Indian stone often shows a combination of luster, purity of water, strength of fire, and perfect "blue-whiteness" of color, such as is absent from Brazilian and South African stones. Moreover, India can claim for its own all the finely colored stones of blue, green, and red, not however yellow diamonds, which come mainly from South Africa.

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Diamond Geology [ 1  India  3  4  5  6  7  8  Brazil  10  11  12  13  14  15  16  17  18  19  20  Borneo  22   South Africa  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  Venezuela, Guyana  42  Australia  44  Argyle  Congo  46  47  48  49  50  51  52  53  54  55  Angola  57  58  59  Guinea  ]


Related links: Diamonds: Large and Famous   Properties   Geology and Mining Diamond Cutting Gem Cutting Diamond Trade  Values of diamonds
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This document is in the public domain.

March, 2011