The 1,898 hectare Liberty property is an early-stage copper-molybdenum (Cu-Mo) porphyry target located in the Cariboo Mining district, approximately 60 km northwest of Quesnel, BC. The property is road accessible by an extensive network of well-maintained Forest Service Roads.
The Liberty property is located along the western edge of the Cache Creek terrane, which hosts numerous Cu-Mo porphyry deposits, such as Taseko’s Gibraltar Mine, which is the second largest open-pit copper mine in Canada. The Gibraltar Mine contains 6.4 billion pounds of copper from past production and current reserves. The current reserve has an average copper grade of 0.24% and a cut-off grade of 0.15% Cu.
The primary focus at the Liberty property is a Mesozoic Cu-Mo porphyry target, defined by coincident Cu, Mo, gold (Au), and silver (Ag) mobile metal ion (MMI) soil and induced polarization (IP) chargeability anomalies located on the margin of a poly-phase granitic stock. Historic drilling in the 1960s by Rio Tinto, to the south of the modern coincident IP and geochemical anomaly, returned an assay result of 123.1 m of 0.11% Cu and 0.04% MoS2, from the top of bedrock to the end of hole.
In addition to the porphyry target, the Liberty property also hosts Cu-skarn and Au-Ag epithermal targets, which are often genetically related to porphyry deposits.
Location / Infrastructure
The Liberty property is located in central British Columbia, approximately 60 km northwest of Quesnel, BC. A series of Forestry Service Roads transect the property. The property is located in the Fraser Plateau, consisting of gently rolling hills, with elevations ranging from 850 m to 1300 m above sea level. Climate in the area is typical of central BC, where summers are warm and dry and winters are cold with little snow. This combination of infrastructure and climate allows for year-round access to the property.
The first documented exploration on the property occurred from 1967 to 1971. Rio Tinto staked the claims due to anomalous Cu in stream sediment samples. They conducted work consisting of soil sampling, IP, trenching, and diamond drilling exploring for porphyry and shear-hosted Cu.
The work culminated in a ~1,000 m diamond drilling program in 1969, which mostly focused on the shear-hosted Cu mineralization (Cu-skarn target) toward the south of the property. However, a few holes also targeted the more northern porphyry target. The northern most drillhole (DDH-A8) returned 123.1 m of 0.11% Cu and 0.04% MoS2 from the top of bedrock (29 m) to the end of hole. Drilling to the south of this hole intersected granodiorite with abundant pyrite, which is interpreted to be part of the outer phyllic zone.
The project remained dormant until 1997, when William Poole staked the area. Between 1997 and 2003 prospecting found wollastonite skar, polymetallic vein, vein-hosted gold, and talc-magnesite showings.
In 2011 and 2012 and IP and MMI soil survey were conducted over the porphyry target, defining a coincident Cu-Mo±Au±Ag soil and IP chargeability anomaly atop a Mesozoic aged pluton.
Trenching in 2013 was designed to test the surface exposure. Deep overburden prevented many trenches from reaching bedrock. However, those that did encountered chlorite-altered diorite with disseminated chalcopyrite, assaying up to 0.39% Cu and continuous ship sample of 0.11% Cu over 10 m.
The property changed ownership a few times since 2013, with minimal work being completed. Work during this time included a single IP line and biogeochemical sampling atop the porphyry target.
Geology and Mineralization
The Liberty property covers a moderate-sized polyphase granodiorite to diorite pluton (~8 km long and 2-4 km wide) Jurassic to Cretaceous in age. The pluton has intruded into the volcanic and sedimentary rocks of the Mississippian to Triassic aged Cache Creek Group. To the east of the property, Eocene-aged Endako Group volcanic rocks unconformably overly the Cache Creek Group and granodiorite pluton. Chilcotin Group basalts are present along the western margin of the claims. Approximately 90% of the property is covered by unconsolidated glacial tills from Pliestocene glaciation.
With limited exposure on the property, most geological information has been gleaned from historic drilling and trenching. Descriptions from the historic drilling and trenching indicate disseminated pyrite, chalcopyrite, and molybdenite occur in the granodiorite pluton. The most northerly of holes from this program encountered 123.1 m of 0.11% Cu and 0.04% MoS2 from the top of sampling at 29.3 m to the bottom of the hole at 152.4 m. This hole is believed to have been drilled at the southern end of a presently defined the MMI and IP anomaly.
MMI soil sampling in 2011 and 2012 defined a 1,750 m by 750 m northwest trending Cu-Mo±Au±Ag soil anomaly. The boundaries of this anomaly display elevated Cd, U, and Zn, which is a common feature of the distal portions of porphyry systems. A second MMI anomaly also occurs ~600 m to the southwest, principally defined by elevated Cu-An-Ag in soil.
Ground-based IP and magnetic surveys have also helped to characterize the primary target at Liberty. Coincident chargeability and resistivity highs were defined with IP, overlapping with the MMI soil anomaly. The chargeability high is interpreted to be caused by disseminated sulphide minerals, such as pyrite and chalcopyrite. The resistivity high could be caused by felsic intrusive rocks, such as the granitic pluton. In addition, there is a noticeable magnetic gradient across the target, with higher magnetic responses to the west and lower to the east. Magnetic destructive alteration, such as phyllic alteration could cause the magnetic low, which corresponds with the IP chargeability high. Whereas, magnetite-rich alteration, such as potassic alteration, may cause the magnetic high, which corresponds with some of the highest MMI soil anomalies.