GR Silver Mining (TSX-V:GRSL) Ltd has announced high-grade silver results from underground infill drilling at the Plomosas Project in Sinaloa State, Mexico.
The results continue to support the potential to increase silver grades at the mine, the company said. Drilling targeted high-grade silver (Ag) mineralization in the upper levels of the underground workings, in areas where unsampled intervals from historical drill holes within the 2021 resource block model were previously assigned zero values.
“The 2022 infill drill program at the Plomosas Mine has been carefully designed to address upside potential in the resource block model. It has been our thesis that historical sampling lacked detail in some unmined areas resulting in the adoption of zero grade in unsampled drill hole intervals in the current resource model,” the company's chairman and CEO, Eric Zaunscherb said in a statement.
READ: GR Silver says high-grade silver results may enhance resource estimation at Plomosas
“This is supported by the observation that current resource model grades in areas already mined are lower than suggested by historical production grades. Further, it is very encouraging to see such high-grade Ag results confirming the existence of new, high-grade Ag zones associated with previously ignored cross-cutting structures. It is highly satisfying to see further proof of concept on both themes, with the potential for a commensurate re-rating," he added.
The underground infill drilling program started in March 2022 and is ongoing. The drill holes are predominantly short holes planned to target zones where recent geological mapping identified opportunities to improve the 2021 NI 43-101 mineral resource block model silver grade, utilizing areas of the underground development that provide good access, the company said.
It noted that a total of 13 holes have been completed underground to date in 2022. These intervals confirm consistent high-grade silver mineralization and have also delineated new mineralized zones in areas not previously drilled. Upon completion of the underground infill drill program in Q4, 2022, the company anticipates commencing a resource upgrade for the Plomosas Mine Area.
Highlights include:
- PLIP22-013: 6.5 metres (m) at 1,458 grames per ton (g/t) Ag (1,485 g/t AgEq), including 0.9m at 3,118 g/t Ag (3,266 g/t AgEq)
- PLIP22-012: 14.0 m at 146 g/t Ag, including 0.4m at 2,474 g/t Ag (2,542 g/t AgEq)
- PLIP22-011: 2.9m at 190 g/t Ag, including 0.4m at 626 g/t Ag
- PLIP22-010: 8.3m at 100 g/t Ag
The drill holes PLIP22-10, PLIP22-11, PLIP22-12 and PLIP22-13 successfully discovered wide, high-grade silver mineralization hosted by hydrothermal breccias located in the hanging wall of the previously mined polymetallic (Ag-Au-Pb-Zn) hydrothermal Plomosas Breccia
This recently mapped zone is located in a section of the Plomosas Mine where the company initially defined prospective NE-trending faults with potential to host additional silver-gold only mineralization. These zones were not previously the subject of significant exploration due to the focus on base metals in the historical plant flowsheet. Historical production, and hence exploration, targeted lead-zinc-rich mineralization at the Plomosas Mine.
Meanwhile, the drill holes from PLIP22-01 to PLIP22-09 consistently intersected high-grade silver-gold mineralization hosted in a polymetallic hydrothermal breccia. All nine holes indicate the presence of multiple hydrothermal zones with silver results generally more than 200 g/t silver and individual gold grades up to 4.5 g/t gold in locations drilled along strike on the 1025 RL level.
GR Silver Mining is a Canadian-based, Mexico-focused junior mineral exploration company engaged in cost-effective silver-gold resource expansion on its 100%-owned assets, located on the eastern edge of the Rosario Mining District, in the southeast of Sinaloa State, Mexico.
Contact the author at jon.hopkins@proactiveinvestors.com