Ramgiri Belt

hutti-belt-figure-1

 

The Ramagiri RP block comprises the well known 13 km long Ramagiri Gold Field (RGF) that was a scene of intensive underground mining activity by the Britishers in the early part of the last century. The 13 km tract had mines over several rich shoots. Three main mining ventures in this tract produced about 176,338 ounces of gold at a recovered grade of around 15 g/t from high-grade veins in the years 1910 to 1927. Until April 2001, the Government of India owned Bharat Gold Mines Ltd. (BGML) was operating the underground Yeppamana Mine in the RGF. The GSI, following a drilling programme, has reported gold resources of all categories from the RGF that includes 590,000 t of ore @ 3.7 g/t gold and an inferred resource of 3.96 million tonnes of ore of an average grade varying from 1.32 g/t to 5.6 g/t.

Exploration undertaken to date has provided new targets in the southern and western parts of the belt. On the basis of some 613 geo-chem samples including stream sediments, rock-chips, soil and channel rock-chips, 3 blocks have been identified as worthy of detailed exploration by drilling. These are:

1) Ramagiri Gold Field block (RGF) – 20 sq km area
2) Boksampalle block – 17 sq km area
3) Ramagiri west block – 18 sq km area

PL applications filed on the first two blocks are under processing by the Govt. of Andhra Pradesh. The extension of the BGML’s lease hold, the Power House mine and the South Jibutil mine fall within our 20 sq km Ramagiri Gold Field P.L. block.

A. Ramagiri Gold Fields (RGF):

The Yappamana and Gantlappa mines

The Yeppamana was operated until April 2004 by BGML. The Gantlappa mine produced 12,000t of ore at 8g/t. Detailed drilling by the GSI in the late 60s reported the presence of several ore shoots. A resource of 1.14 mt of ore of 3.32 to 5.6 g/t grade up to a depth of 300m has been estimated. The average width reported is 1.98 m. Details are contained in unpublished reports of GSI, which we propose to purchase as soon as the Govt. grants the Prospecting Licence.

 

a) The Power House Mine

The power House mine is located to the south of the Gantalappa mine. It is reported to have produced about 4000t of ore with 17.6g/t. The GSI tested this mine with 12 diamond drill holes and reported narrow widths of 0.18 to 0.29m having grades of 8.4 to 52.7g/t.

b) South Jibutil Mine

Further south of Power House Mine several shafts exist. The main shoot yielded 13.6 to 37.5g/t. There are two ore shoots, which join near the 800m level. The ore stopped out was of the order of 60,000t of 11.2g/t and 6,500t of 35.2g/t. This mine has contributed to the main production from this sector during the British time. Channel sampling involving the collection of 90 samples in 13 channels of the exposed mineralized zone and wall rocks of veins in Jibutil area have shown anomalous gold in the range of 100 ppb to 999 ppb and 5 samples >1 g/t. A 50 cm wide quartz vein with sulphides analysed 1.67 to 3.83 ppm of gold. Rock-chip sampling from an outcrop NE of Shaft No. 5 has analysed 2 g/t Au. Dump samples from the old mines reported 3 to 17 g/t. Detailed prospecting is proposed to be undertaken in the Jibutil area in the light of these encouraging results.

hutti-belt-figure-1

B. Boksampalle block: mineralisation in sheared granites

Boksampalle is situated close to the southern termination of the Ramagiri belt. The prospect is 2 km long containing a series of gold bearing sulphidic quartz veins traversing fractured granite. Within this tract there is a wide zone of mineralisation, 4.2 m to 62.12m, over a length of 350 m. Resampling of surface outcrops has revealed 3 parallel zones of vein quartz in fractured granite. The central quartz vein is 2-5m wide. Six randomly collected rock-chip samples from different veins assayed 0.23 g/t to 3.49 g/t. The vein quartz zone is 2 km long with the surface width of 2 to 25m within a narrow and steep sheet of granite intruding metabasalt. GSI’s drilling showed a poor average grade of 0.48 g/t within which there are better intercepts 6.29m at 2.54g/t and 9.18m at 1.20g/t. In GSI’s bore hole BH-1, a series of quartz veins in sheared granite were reported with an average gold value of 0.47g/t for 26.92m.

The above review of the exploration data on Boksampalle suggests that it is worth drilling the area to probe deeper levels to establish mineable ore shoots if any in the area.

a) Boksampalle North Prospect

Surface rock chip sampling of vein quartz, from shear zones in basic volcanics, has been carried out at various locations on this prospect. Three separate shear zones yielded best assays of 15.6 g/t, 13.8 g/t and 8.89 g/t. Follow- up sampling is in progress.

Conclusion on Ramagiri belt

The entire Ramagiri belt is very much under-explored. The high grade of historic production from shoots (15 g/t gold) makes this area an important target for exploration, to trace the depth continuity of the known ore shoots and to locate new ore shoots.

All the ore shoots discovered in the Ramagiri Goldfield by the old miners, including the recent BGML operations, were below the ancient workings. These cover only a portion of the total length of the field. There are several parallel lodes in the field. Much of the ground between the mines has largely remained unexplored.