The Hog Heaven Ag-Au-Cu-Pb-Zn Project is an advanced stage exploration property, which historically produced high-grade silver, gold, lead and copper from near surface, high-sulphidation epithermal occurrences. Between 1929 and 1975, Anaconda Copper Mining and lessees produced 6.87M troy oz Ag, 3,300 troy oz Au, 33.7M lbs Pb, and 0.4M lbs Cu from 0.29 million tons of Direct Ship Ore, grading 23.6 troy ounces per ton Ag overall. Hog Heaven is actively being explored for its copper-porphyry potential at depth by the operator, Ivanhoe Electric Inc.
Joint Venture
On March 2, 2021, Brixton & High Power Exploration (now Ivanhoe Electric Inc.) signed a USD$44.5 million definitive agreement for an earn-in joint venture on the Hog Heaven Project. If Ivanhoe Electric meets their earn-in obligations within the 11 year term, they will have an 75% interest in the Hog Heaven Project.
Ivanhoe Electric is a U.S.-based mineral exploration and development company led by Mr. Robert Friedland. For more details, please see Brixton’s press release, dated Mar 2, 2021.
Location
The Hog Heaven Project is located within Flathead County, in northwestern Montana, 40 kilometers southwest of Kalispell and 215 kilometers east of Spokane, Washington. The Hog Heaven Property encompasses 24.34km2 of private land. The Hog Heaven district consists of several high sulfidation epithermal mineral deposits and prospects as well as several now-closed mines, including the Flathead Mine.
History
1913 Anaconda sunk an exploration shaft on the Flathead Mine (Main Mine)
1929 – 1946 Anaconda Copper Mining produced 6.41M troy ounces Ag, 3,100 oz Au, 30.4M lbs Pb, and 0.4M lbs Cu from 241,069 short tons of Direct Ship Ore grading 26.6 troy ounces per ton silver
1963 – 1975 The Flathead Mine produced 0.46M oz Ag and 3.38M lbs Pb from 49,700 short tons, averaging 9.35 troy ounces per ton silver
1994 – 2017 Pan American Silver maintained Operating Permit; in 1996 Kennecott drilled 2 holes, geophysics-geochemistry-mapping
2017 Brixton acquired 100% interest, subject to a 1.5% NSR held by Maverix Metals (now Triple Flag Precious Metals)
2020 Brixton’s maiden 7 collar drill program, 1,400 meters total
2021 Brixton signed a Definitive Earn-in Option agreement with High Power Exploration (now Ivanhoe Electric) for USD$44.5 Million
Drilling
Historically, over 700 rotary, reverse circulation and diamond drill holes have been collared on the Hog Heaven Property, totalling almost 59 kilometers. Even though high-grade copper, lead and zinc have been mined on the property, a significant portion of the drill dataset was only evaluated for gold and silver. Prior to starting their drill program in 2022, Ivanhoe Electric re-logged 14,500 meters of this historic core and assayed 3,600 drill core pulp samples using a full suite of elements to aid in planning and improve modelling.
Earlier exploration and mine work on the Hog Heaven was generally constrained to within 300 meters of the surface. Taking into consideration the large alteration footprint on the property and the high-grades and multiple mineralized centers, Ivanhoe Electric’s work has focussed on the underexplored potential at depth. Using their proprietary Typhoon™ electromagnetic survey technology to assist in targeting, the operator has completed 15 drill holes since 2022, drilling over 13,500 meters to date (April 2024). Ivanhoe Electric’s program has been successful at identifying new mineralized zones at depth, including an 82m interval of 0.63% Cu, 0.32g/t Au, 37.76g/t Ag, 0.06% Pb and 0.15% Zn starting at 568.00 meters depth, including 15.75 meters of 1.97% Cu, 0.72g/t Au and 97.1 g/t Ag (note that the copper values for these intervals were capped at 10% Cu due to a 1.13 meter interval that contained 21.7% Cu).
As of April 2024, Ivanhoe Electric continues to drill with one rig on the Hog Heaven property. Please see their website for a listing of available drill results: https://ivanhoeelectric.com/electric-metals/hog-heaven/
Geology
The Hog Heaven district is comprised of a package of Oligocene felsic volcanic rocks that unconformably overlie Proterozoic Belt Supergroup rocks. The volcanic rocks include dacitic to rhyolitic flow-domes, dykes, ash-flows, volcaniclastics and associated diatremes.
Mineralization
Historically, exploration and mining on the Hog Heaven property have been focussed entirely on near-surface, high-sulphidation epithermal Ag-Au-Cu-Pb-Zn occurrences. Several of these epithermal deposits and prospects exist on the property, including the Flathead mine which produced approximately 241,000 short tons of direct-ship ore averaging 26.6 troy oz/ton silver, from 1929 to 1946. Mineralization is hosted within veins and stockworks, semi-massive to massive sulphide strata-bound lenses, and diatreme breccias. Ore minerals are predominantly pyrite, galena and sphalerite, with enargite, argentite, native silver and tetrahedrite occurring locally. There is strong argillic alteration throughout the district.
Early drilling by Ivanhoe Electric below these epithermal zones identified several porphyry system indicators including: fragments of a porphyritic intrusion cut by quartz-pyrite stockwork within a breccia (HHD-007 at 772m) and sub-vertical pyrite-enargite veins cutting a diatreme breccia (HHD-005 at 903.5m). Recent drilling west of the Flathead Mine has identified massive enargite-pyrite infill and replacement, with grades up to 21.7% Cu, 3.94 g/t Au and 519 g/t Ag over 1.13 meters (HHD-014 at 631.55m).
Between 1929 and 1975, Anaconda Copper Mining and lessees produced 6.87M troy oz Ag, 3,300 troy oz Au, 33.7M lbs Pb, and 0.4M lbs Cu from 0.29 million tons of Direct Ship Ore, grading 23.6 troy ounces per ton Ag overall.
The road accessible property is located in Flathead County, a 30 mile drive southwest of the town of Kalispell, northwestern Montana, USA.