The company's president and CEO, Darren Klinck said the results, including "some of the highest gold and silver grades we have seen since the start of the program", added weight to the company's belief that the former Goldcorp-developed underground mine (which didn't get into production before Goldcorp sold to Bluestone) had a more complex and pervasive vein system than previous resource mapping showed.

"The drilling continues to validate our understanding and confidence in the new geological interpretation of the deposit and will be fundamental to the planned updated resource estimate and engineering studies concurrent with our feasibility study," Klinck said.

New drill intercepts include 7m of 17.2 grams per tonne gold and 94.9g/t silver, 8.3m of 32.7g/t gold and 79.6g/t silver, 15m of 16.7g/t gold and 105.4g/t silver, and 9.3m of 14.3g/t gold and 68.5g/t silver.

Two of the latest holes were fan holes that intercepted "multiple zones of parallel veins from approximately 15 meters below the South Ramp underground workings".

Bluestone has 100% of the Cerro Blanco gold and Mita geothermal projects. It expects to complete a feasibility study on the former by the end of this calendar year.

Its earlier preliminary economic assessment had a US$170.8 million investment setting up Cerro Blanco to produce 952,000oz of gold and 3.14Moz of silver over nine years at US$490/oz AISC for gold produced.

Bluestone had a market capitalisation this week of C$83 million, trading at C$1.30. The stock was at 50c in mid-April last year, but touched $1.74 in June.