Kurnool District: A conglomerate bed about ten meters thick is found here. Diamonds occurred and still appear in the layers of this bed as small blue, green or yellow grains. The old kingdoms of Bijapur and Golconda had 38 diamond mines close to the Krishna river and other mines have also been reported by travelers. In general the mines were located in alluvium or river gravel, sedimentary rocks or archean crystalline rocks. The other areas where stones were found after rain were near the Banganapalle conglomerates. The layers were mines by sinking shafts of about 3-5 meters depth with galleries going along the seam. However, these diamonds were of poor quality being colored small and highly flowed.
Mines at Komarulu and Dhone have produced diamonds of medium quality but on the other hand the Lanjapolur stones were of a better grade. However the mines generated no revenue since 1813. These mines at Ramallakota and Varakaru produced stones of excellent quality, though of very small size. According to Tavernier, these stones were extracted from sand or the surrounding earth that occupied narrow veins in the rock. Near Virayapalle the diamonds yield was incredibly large, one carat of flawless and well formed gemstones from seven tones of ore. But since 1910 there has apparently been no output or even mining operations in this area.
Guntur District: the largest mining operations were at Kollur and the location of this mine was referred to by Tavernier as “color” and sometimes as Quolore. In 1645 it employed nearly sixty-thousand persons in very productive mining operations. Three decade later, the tract appeared to have been exhausted and it is now deserted. Legend has it that the Kohinoor or the great Mogul was found here.
Krishna District: The mines at Partiala, north-west of Vijayawada, yielded mainly yellowish or reddish colored diamonds in gravel some ten meters below the surface. The description by Scott Tallies with the procedures described by Tavernier at Kollur except for the curious fact that at Partiala, women were not allowed near the mines. Contemporary accounts state that the famous pit diamond came from one of these mines. The Kodavatakallu mines between the Muniair and the Krishna rivers produced several bullock cart loads of diamonds according to local lore.
Bengal: The Ain-i-Akbari refers to a diamond mines near Hirpah in Burdwasdistrict but this is now discounted for lack of confirmation.
Bihar: The ancient work, Tuzuk-i-Jahangiri mentions a diamond field near the source of the Sunk river, south of the watershed of the Koel river in Ranchi district. However, no stones of any value have been found here in recent times. Tavernier refers to the Soumelapur mines close to the village of Simh in Palamau district, where the sands of the Koel river were prospected for diamonds and where large stones were occasionally found.
Madhya Pradesh: Abdul Fazal mentions the mines at Wairagarh. By 1827 these very productive mines were exhausted and by 1843 the abandoned workings were barely visible. Lying between the Panna shale and the upper kaimur sandstone, the diamond containing layer in Panna district is a conglomerate of about 2m thickness. Diamonds occur in the joints and bedding plains of the kaimur sandstones rocks or in the alluvial cover. North-East of Itwa the bed is localized, where reports have it that diamonds are found in the Majhgawan area occur in a volcanic neck filled with agglomerate tuff. The soft and very friable volcanic rock in which diamonds occur is yellow to yellowish green and is a 100km long and about 20km wide. This volcanic pipe is opined to be the main source of diamonds and other such volcanic pipes are thought to exist in the area. Mining in the Panna fields is done by agriculturists between February and June, with claims of 10sqm each. The prospects for diamond mining were reported to be good in 1954, but nothing further was done. The Panna mines are now the only visible Indian source of diamonds for industrial and gem varieties. The production was about 5% lower in 1971 than in the previous year. The total reserves of diamonds are estimated to be 410000 carats in these regions.
Baraunda: Diamonds were once plentiful in this area on the north bank of the Chahala river, but mining ceased after a find of 12-24 stones of which one weight about 118 carats.
Orissa: The gravel bed of the Ib, a tributary of the Mahanadi river a few miles from Sambalpur as well as other tributaries of the Mahanadi as far up as the Mand river have been dredged successfully for diamonds. Between 1804 and 1818 twenty stones were found of which the largest rough found in 1809, weighed 218 carats. The sands from the streams near Bpndesor in Kalahandi have yielded minute diamonds, but a systematic search for larger stones had not been made.
Since 1926, the Panna diamond mining syndicate, the Mahalakshmi diamond mine works and Charkari mining works were the main companies involved in diamond mining. No serious and systematic surveys were made by these companies to look for diamonds. In 1954 Russian assistance was sought for a plan for modernization that would cost 6 million rupees and handle six thousand to seven thousand tones of ore a day, but this effort seems to have failed. At present, any diamonds that may be found must be handed over to the government of India. The diamond officer in Panna records the weight and characteristics of the stones before they are auctioned. The person who found the stones then gets a reward of one quarter of the sale price. Panna production is presently very small in comparison with world output, but the diamonds are on the average priced higher than those from South Africa.
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