DIAMOND IN INDIA
4. The Sambalpur Group on the Mahanadi River.
This group is situated a good distance to the northwest of the previous group, and lies between latitude 21º and 22º north, in the Central Provinces. The diamonds known to the ancients may have been those of the Mahanadi River, the diamond river mentioned by Ptolemy being supposed to be in this district, and being, in fact, identified by many authors with the Mahanadi River itself. The occurrence of diamond is limited to the neighborhood of Sambalpur, no other part of the river having given any yield. The mining district extends over a fertile plain, which at the town of Sambalpur stands 451 feet above sea level, and forms the stretch of land between the Mahanadi and Brahmani Rivers. The date of the first discovery of stones here is unknown, but Sambalpur has been a familiar diamond locality since very remote times.
The diamonds are found for the most part in the neighborhood of the confluences of the Mahanadi with some of the tributaries on its left bank. These tributaries, which flow into the river from the north, rise in the Barapahar hills; one of these, which joins the Mahanadi a little above Sambalpur, is the Ebe, and is sometimes considered to be the diamond river of the ancients, but whereas the occurrence of diamonds here has not been proved, there is no doubt as to their occurrence in the Mahanadi valley. In former times the stones were collected in the riverbeds after the rainy season. They were found in the Mahanadi River only on the left bank, never on the right, and not higher up than where the Manda tributary enters the main river at Chandapur; according to some accounts, which however are probably incorrect, the mouth of the Ebe is the furthest up-stream limit to the occurrence of diamonds, and this river is therefore often considered to be the one down which the diamonds were transported into the Mahanadi. The whole diamond-bearing stretch of the Mahanadi is about twenty-eight miles long, being limited eastwards by a bend in the river at Sonpur. One of the most important points on the Mahanadi appears to have been Hira Khund, a name which signifies diamond mine; this is an island about four miles long, which lies near the village of Jhunan and divides the river into two branches. Every year, about the end of March or later, that is, in the dry season when the river is very low, people flocked in thousands to this place to search for diamonds. The branch of the river on the north side of the island was dammed up, and the diamond-bearing sands and gravels of the riverbed dug out and washed for diamonds by the women. The southern branch of the river was never worked for diamonds, although in the opinion of s6me experienced persons, they were there to be found, possibly in greater numbers than in the north branch. The damming-up of the south branch would, however, present greater difficulty since the volume of water here is greater and the current stronger than in the north branch.
Diamonds are found near Sambalpur in a tough, reddish mud containing sand and gravel. This material is probably the weathered product of the rocks of the Barapahar hills brought down by the rivers, which rise there. The solid rock of this region is not, as far as is known, worked for diamonds although it is very similar to the rocks, which in all parts of southern India yield the precious stone. A certain number of diamonds are found in the small streams, which rise in this neighborhood, near Raigrh, Jushpur, and Gangpur.
Large stones are said to have been found in the Mahanadi with some frequency. The largest was found at the island of Hira Khund in 1809 it weighed 210.6 carats, but ranked only as a stone of the third water, and its subsequent history is unknown. Generally speaking the stones found here were very good in quality, the diamonds of the Mahanadi and of Chutia Nagpur ranking amongst the finest and purest of Indian stones. In the Mahanadi, diamonds are associated with pebbles of beryl, topaz, garnet, carnelian, amethyst, and quartz these minerals, however, have probably been derived from the granite and gneiss through which the river flows and not from the mother-rock of the diamond. The Mahanadi yields also a fair amount of good, which is separated from the river sands and gravels by washing at the same time, as are the diamonds.
At the present day, diamonds are found in this district only occasionally systematic work was carried on down to about the year 1850, when, owing to the poorness of the yield, it was discontinued.
The mines of Wairagarh, in the Chanda district of the Central Provinces, may be conveniently described with this group. They are about eighty miles southeast of Nagpur, very ancient, and identical with those mentioned by Tavernier under the name Beiragarh; their identity with those of Vena (Wainganga) is uncertain. The remains of these mines are still to be seen on the Sath River, a tributary of the Kophraguri, itself a tributary of the Wainganga. The mines were formerly rich, but have been abandoned since 1821. The stones lie in a red or yellow, sandy, laterite-like earth, but the rock from which this alluvial material was originally derived is unknown. According to Professor V. Ball, this diamond-bearing stratum has a far wider distribution than is generally supposed, and will perhaps at some future time become of importance.
To the north of the Sambalpur district, in the Chutia Nagpur (the ancient Kokrah) division of Bengal, diamond mines were formerly worked. These mines are said to have yielded in the sixteenth and seventeenth centuries many large and fine stones, which are stated to have been obtained from one of the rivers of the district. The identity of this river is not exactly known, but it is supposed to be the Sankh, a tributary on the left side of the Brahmani, also a river in which diamonds have been found but at a later date; even such occasional finds are not now, however, to be made.
In Tavernier's time some famous mines, which were described by him, existed at Sumelpur, but their exact situation is now not known. According to the account of this traveler, the diamonds were here washed from the sands and gravels of the River Gouel. This river is supposed to be identical with the North Koel River, a tributary of the Son, which in its turn flows into the Ganges, and on the banks of which are the ruins of the ancient town of Semah or Semul, supposed to be identical with Tavernier's Sumelpur (Semelpur). This town must not be confused with Sambalpur, a town on the Mahanadi River, which has been mentioned above. The stones found in this district were originally derived from the hills forming the watershed of the rivers North Koel and Sankh. Tavernier states that 8000 people were at work in these mines at the time of his visit, in the dry season at the beginning of February. Many other statements respecting the early finds of diamonds in Chutia Nagpur are now regarded as false, having nothing more substantial than fable as their foundation.
Rafal Swiecki, geological engineer email contact
This document is in the public domain.