Exploration And Drilling Results For Hollister Project and Burnstone Mine

Exploration And Drilling Results For Hollister Project and Burnstone Mine 

VANCOUVER, BC – Great Basin Gold Ltd. reports exploration, stope and block delineation results for its Hollister Project and Burnstone Mine. At Hollister, highlights include results from the Velvet target drilling, the emergence of another high grade pay shoot on the Clementine #18 vein structure in the western part of the Hollister orebody, and significant advances in the integration of existing geological and geophysical data with new structural interpretations, leading to a number of new exploration follow-up targets.

At Hollister underground exploration and stope delineation drilling has continued during the first quarter of 2011 (Q1 2011). In total, two exploration holes at the Velvet target, fifteen Blanket exploration holes (totaling 15,487 feet or 4,693 meters) and twenty-four stope delineation holes (totaling 10,080 feet or 3,054 meters) were completed.

Two initial exploration holes have been completed, testing the Velvet target north of the current mine infrastructure. The boreholes were drilled at low angles across the Ordovician basement strata, and were approximately 500 feet (160 meters) below the Tertiary volcanic unconformity. HDB-432 was drilled laterally to 3,383 feet (1,025 meters) and HDB-433 to 2,854 feet (865 meters). Of note, the current Hollister mine development, exposing the Gwenivere and Clementine vein systems, extends vertically from 5,050 to 5,425 feet (1,530 to 1,644 meters) above mean sea level. HDB-432 tested to an elevation of 4,600 feet (1,394 meters) and HDB-432 to 5,000 feet (1,515 meters) above mean sea level.

A number of significant silver assays (5.5 to 7.4 opt Ag, 190 to 255 g/t Ag) with anomalous gold values were received in the 630 to 705-foot (210 to 240-meter) zones. These are interpreted to be southerly extensions of the Gloria vein system some 6,000 feet (1,820 meters) to the north-northwest. The correlation would imply structural continuity with the Gloria vein system and, as such, constitutes a very significant vein extension target, requiring further exploration drilling. The metal zoning is considered indicative of mineralized structures in the lower zones of a Hollister equivalent epithermal mineral system.

Borehole HDB-432 also intersected multiple mineralized vein and silicified zones between 875 and 1,117 feet (265 to 338 meters). HDB-433 intersected similar zones between 1,314 and 2,795 feet (398 to 847 meters). The silicified zones ranged from 2.6 to 28.4 feet (0.8 to 8.6 meters) in width. These zones correlate with existing structural features as well as historic mercury diggings such as Butte #2 and Velvet north of the current mine development. Multi-element geochemical analyses and clay mineralogy studies are in progress. The Velvet targets will be further tested by surface drilling during the upcoming summer field season.

During the quarter fifteen boreholes were completed, testing the extensions of Blanket zone mineralization exposed by trial mining at 3000N 1E; assays from nine boreholes are still awaited. The drilling is indicating structural cutoffs of this mineralization in-line with the structures controlling the Clementine #18 vein pay shoot below. The evaluation strategy for the Blanket zone mineralization is being modified as mining and drilling advance. It is clear that the bulk sample exposures are proving to be a more accurate in evaluating the variable extent of the bonanza grade mineralization. Planned infrastructure will allow ramping up to 5478 level, followed by phased short distance fan drilling.

The close relationship of the development of bonanza grades with underlying high grade ╥pay-shoot╙ epithermal veins is becoming evident. As a consequence, the Blanket drilling program is being modified and extended to test other targets within the mine development.

Nevada Bureau of Land Management (BLM) approvals for surface drilling at Hollister have been received. Budgeting and planning of the surface exploration drilling for Q2-Q3 2011 are now being advanced, and include a further eight boreholes on the Hatter Graben target and surface follow up of the Velvet underground drilling.

At Burnstone infill drilling from surface is being undertaken to tighten up on the evaluation and structural geometry of certain mining blocks.

Underground evaluation is principally effected by channel sampling of exposed sidewalls of development drives and stope panels. Horizontal or shallow dipping cover drilling is undertaken for development control. Over 10,000 channel samples have been taken to date. During Q1, 2,686 channel samples were taken.

The results are in-line with or better than mine development expectations. Although current channel widths are skewed due to the higher number of samples for Block B3 sampling, the Life-of-Mine plan indicates an average channel width of 68 cm.

Surface exploration has recommenced at Burnstone, with the initiation of the shallow basin edge target evaluation program, run under the South Rand Basin Project. Historic surface diggings and limited stoping of the Kimberley Reef is being investigated on the farm Rietbult, approximately 7 kilometers northwest from the Burnstone Mine infrastructure. The first two diamond holes intersected a Kimberley Reef stope approximately 55 meters below surface, and the Kimberley Reef at 87 meters below surface. Assay results are awaited. Previous exploration in the area included historic drilling in the 1960╒s, as well as validation underground channel sampling of reef exposures. This work, albeit restricted in extent, showed the Kimberley Reef to be narrow (10 to 30 cm) but with grades ranging from trace to 35 g/t Au. The current drilling program will test in the order of 4 kilometers of potential strike, with a view to evaluating satellite, shallow, narrow reef/high grade underground development.

Ferdi Dippenaar, Great Basin Gold President and CEO, said, ╥Our decision to continue with exploration at Hollister during 2010 continues to deliver results. The emergence of a new payshoot will deliver short-term benefits, and our work on the larger Hollister Property indicates the existence of a similar orebody to the one currently being trial mined. The geological teams at both Hollister and Burnstone are continuing to hone their evaluation and exploration skills. An excellent geological and structural platform is emerging at Hollister for the discovery of further gold and silver-bearing vein systems. Continued integration of the data available is paying dividends in improving our predictive models. At Burnstone, the team is integrating existing geological information with the detail afforded by underground exposures. This will, in due course, provide real-time updating of the geological and structural models, which will, in turn, assist with short to medium term mine planning.╙

The company╒s address is 108- 1030 West Georgia Street,?Vancouver BC V6E 2Y3.