Drilling Program To Commence At Willow Property
VANCOUVER - Abacus Mining & Exploration Corporation reported that a diamond drilling program is about to commence on its Willow porphyry copper property in the Yerington copper camp, southeast of Reno, Nevada. The Company plans to drill four vertical holes, each to a depth of 600 meters. The holes will be approximate 200-300 meter step outs from past drilling by the Company in 2018. Based on work done by Abacus the target is at least 1.5 km by 1.5 km in size, the Willow porphyry remains essentially untested, and the porphyry center has not yet been identified.
The Yerington camp contains four known porphyry copper-molybdenum (Cu-Mo) deposits, and Abacus’s work points to the existence of a fifth porphyry on Willow, the first major discovery in the camp in over 40 years. All four known copper porphyries are associated with a particular intrusive rock known as the Luhr Hill Granite.
Abacus completed geological, geochemical and geophysical work on Willow beginning in 2017 and then undertook a short core drilling program. This drilling identified the Luhr Hill Granite on Willow with copper values in the 0.1% to 0.2% Cu range along with elevated Mo. This was a key new discovery, as there are no known instances of this granite in the camp without an associated porphyry. The Molybdenum values are a particularly strong indicator that you are close to a porphyry copper center.
The drilling also intersected porphyry dykes and “early halo” quartz veins associated with the Luhr Hill Granite. The early halo quartz veins are significant, as they are found in other porphyry copper deposits in the camp and are also associated with economic porphyry copper deposits worldwide.
The 2018 drill program was designed to test a very small portion of an extensive zone of intense silicic and advanced argillic alteration, marked by coincident geological, geochemical and geophysical signatures typical of a porphyry copper or Cu-Mo deposit. Porphyry copper systems are large in extent, and geochemistry collected from the drilling indicates that a likely porphyry center occurs north of the area initially drilled. The Company’s target is essentially identical to the two largest porphyry deposits in the Yerington camp, namely the past-producing Yerington mine and the undeveloped Ann Mason deposit.
The Company recently engaged a consultant to review the Willow data. He agrees with previous interpretations that Willow clearly has a signature typical of a porphyry copper or Cu-Mo deposit. He also agrees with past recommendations that the property undergo more drilling, as the porphyry center has not yet been identified.
Of the porphyries in the camp, Anaconda mined the Yerington porphyry between 1952 until 1978, producing 1.6 billion pounds of copper. The undeveloped Ann Mason porphyry deposit lies just east of Willow and is held by Hudbay Minerals. In early April of 2021, Hudbay announced an updated PEA on Ann Mason with a revised M&I resource of 2.2 billion tonnes at 0.34% Cu. Nevada Copper is in production at its Pumpkin Hollow skarn (P&P of 572 MT at 0.4% Cu). Quaterra Resources recently announced drilling to support the Prefeasibility Study that is ongoing on their MacArthur oxide copper project (M&I of 159MT at 0.212% Cu).