North of 60 Mining News - The mining newspaper for Alaska and Canada's North

Hecla Mining Company Aug. 6 reported that drilling at Greens Creek has upgraded and expanded the resources in East Ore, NWW and 9A, zones.

East Ore is a zone that comes to surface at the Big Sore outcrop that led to the Greens Creek discovery. Going into 2019, this zone continued to host 454,800 metric tons of indicated resource averaging 12.6 ounces per ton (5.73 million oz) silver, 7.86 percent (35,760 tons) zinc, 2.94 percent (13,390 tons) lead and 0.089 oz/t (40,600 oz) gold; plus 635,000 tons inferred resource averaging 13.48 oz/t (8.57 million oz) silver, 8.06 percent (51,900 tons) zinc, 2.71 percent (17,200 tons) lead and 0.101 oz/t (64,100 oz) gold.

Drilling across a 200-foot section of the central portion of the East Ore zone resource confirm the mineralization.

Strong assay results from this drilling include 16.2 feet of 21.57 oz/ton silver, 8.44 percent zinc, 2.59 percent lead and 0.25 oz/ton gold; and 9.5 feet of 64.09 oz/ton silver, 8.08 percent zinc, 2.1 percent lead and 0.18 oz/ton gold, over 9.5 feet.

Hecla plans to continue drilling East Ore zone for the balance of 2019 with the goal of continuing to upgrade the resources there to the north.

Drilling continued at the southern-most and lower portions of the NWW Zone evaluating over 400 feet of strike length.

NWW is a fault separated extension of the East and West zones at Greens Creek.

Going into 2019, NWW hosted 260,900 tons of measured resource averaging 8.3 oz/t (2.17 million oz) silver, 9.9 percent (25,830 tons) zinc, 2.52 percent (6,570 tons) lead and 0.118 oz/t (30,800 oz) gold; 740,200 metric tons of indicated resource averaging 10.08 oz/t (7.46 million oz) silver, 8.17 percent (60,500 tons) zinc, 2.63 percent (19,430 tons) lead and 0.095 oz/t (70,100 oz) gold; plus 387,000 tons inferred resource averaging 15.59 oz/t (6.03 million oz) silver, 8.09 percent (31,300 tons) zinc, 3.24 percent (12,540 tons) lead and 0.081 oz/t (31,500 oz) gold.

Recent results from drilling at NWW include 5.8 feet averaging 40 oz/ton silver, 29.07 percent zinc, 14.56 percent lead and 0.04 oz/ton gold; and 1.4 feet of 130.44 oz/ton silver, 8.33 percent zinc, 5.2 percent lead and 0.28 oz/ton gold.

This drilling identified with a precious metal-rich zone west of the current resource and a base metal-rich zone extending beyond the resource. This drilling also shows a second band of mineralization that extends to the east.

Definition drilling of the 9A zone targeted 200 feet of strike length in the middle of the zone.

Lying between the Maki and Kahuna faults, 9A Zone is the most structurally dismembered zone at Greens Creek. Restoration of the movement along the Maki fault suggests that the 9A Zone represents the fault-bounded connection between the East and West zones to the south and NWW to the north.

Going into 2019, 9A hosted 456,500 metric tons of indicated resource averaging 10.68 oz ton (4.88 million oz) silver, 9.26 percent (42,250 tons) zinc, 3.76 percent (17,150 tons) lead and 0.077 oz/t (35,300 oz) gold; plus 389,000 tons inferred resource averaging 11.73 oz/t (4.56 million oz) silver, 9.41 percent (36,600 tons) zinc, 4.17 percent (16,230 tons) lead and 0.079 oz/t (30,600 oz) gold.

Recent drilling at 9A has cut 20.1 feet averaging 29.41 oz/ton silver, 8.88 percent zinc, 4.31 percent lead and 0.35 oz/ton gold; and 10 feet of 35.75 oz/ton silver, 13.65 percent zinc, 6.76 percent lead and 0.37 oz/ton gold.

Hecla said the 9A zone is structurally complex and multiple drill holes intersected mineralization across several bands.

Definition drilling for the remainder of 2019 is planned to focus on the East Ore, 9A and 200 South zones.

Definition drilling of the Upper Plate has stopped but is expected to resume in the fourth quarter. Exploration drilling later in 2019 is planned to target the southern extension of the 200 South Zone and the Deep Southwest.

–SHANE LASLEY