THE DIAMOND MINES OF INDIA 165
The
diamonds of this district are found chiefly in a surface deposit, and
it was evidently the custom to search for them after heavy rains, which
would wash them out of the ground. In the modern operations, pits
separated by narrow walls, some of them cut to steps leading to the
bottom, are dug down into the diamondifer-ous deposit, the earth being
carried up on the heads of natives, in bowls similar to the carimbe of
Brazil, for washing. A substratum of rock similar to the Kimber-lite of
Africa was reached under the deposit of diamond-bearing earth, but
nothing has been developed to warÂrant an expectation that the African
chimneys will be duplicated. A scientist thought he had discovered the
matrix of the Indian diamonds in numerous veins of eruptive material
which channel the underlying gneiss of this district, but the claim was
not substantiated. About thirty to fifty miles east of Wajrah Karur,
are a number of deserted mines which yielded at one time many diamonds
and were worked with good success through the first quarter of the
nineteenth century. At Banaganpilly, in this neighborhood, are mines;
also at Nandial a little to the northeast, and at Karnul or Kurnul
about due north. The diamond-bearing stratum of this section of India
is named after Banaganpilly.
West
of half way between Banaganpilly and Karnul are mines supposed to be
identical with the mines of Raolconda, which in Tavernier's time were
celebrated for their richness. They had been worked then for several
centuries, but later passed out of knowledge. Of late years the
deposit, which lies deep but is quite extensive, has been worked again
spasmodically. They are known now as the Ramulkota mines.
