The Revenue Deposit area is centered across, and encompasses, Revenue Creek, a legendary placer gold creek in the Dawson Range. It occupies the central and eastern portion of a 24 km2 gold, copper and molybdenum soil anomaly with values that exceed 1000 ppb gold and 500 ppm copper. The Nucleus deposit is located 2.5 km to the west of Revenue within the same multi-element soil geochemical anomaly.
Figure 1. Gold and Copper Anomalies click here for pdf
The dominant geological feature at Revenue is a roughly elliptical 1100 X 500 meter diatreme (Figure 2). Mineralization related to the diatreme includes quartz-sulfide veining and breccias, which are focused near the diatreme contact with biotite-granite host rock, and within peripheral pyroclastic dykes. The circumference of the diatreme defines strong Cu, Au and Mo in soil anomalies, and the diatreme itself is a geophysical anomaly defining magnetic and chargeability lows. Work in 2016 identified that some of the longest and consistently high grade drill intersections at Revenue are genetically related to the host biotite granite and predate emplacement of the diatreme (Table 1). These mineralized zones consist of sheeted and stockwork quartz-sulfide veins (Figure 3a) that have high-temperature K-feldspar altered selvages (Figure 3b) and are consistent with a porphyry deposit model.
Figure 2. Revenue Geology and Blue Sky Exploration Target click here for pdf
Table 1. Significant Gold, Copper, Silver and Molybdenum
Intercepts. Red text indicates that the mineralization, at least in part, predates diatreme emplacement.
|From||To||Length (m)1||Au (g/t)||Ag (g/t)||Cu (%)||Mo (%)|
1 True widths unknown
Mineralization at Revenue resulted from 1) an early stage porphyry-style event that is genetically related to a biotite granite stock, and 2) superimposed mineralization related to subsequent emplacement of the Revenue diatreme. Because the geology and mineralization related to the diatreme is most conspicuous, it has been the focus of historical exploration. In 2017, in addition to continuing to explore for high-grade breccias around the Revenue diatreme, a 2.7 km2 area (the Blue Sky zone), which extends 1.7 km southeast from the Revenue Diatreme, will be explored for extensions of the high-grade porphyry Cu-Au-Mo mineralization encountered in drill holes RVD11-019, RVD11-022, and RVD11-028 (Figure 2 and Table 1). The Blue Sky zone overlies the same biotite granite that hosts porphyry style mineralization near the diatreme, and is characterized by multi-element Cu-Mo±Au in soil anomalies and several chargeability highs.
The current (Dec. 15, 2014) inferred resource for the Revenue deposit is reported at a cut-off grade of 0.5g/t AuEq. The total resource estimate at a AuEq cut-off grade of 0.50g/t is 80.8 million tonnes of mineralized material containing 1.01 million ounces gold, 8.96 million ounces silver, 241 million pounds of copper, and 83 million pounds of molybdenum grading 0.39g/t gold, 3.45g/t silver, 0.14% copper and 0.05% molybdenum (Table 2).
Results of preliminary metallurgical work by SGS in 2012 concluded that with a primary grind size of 120 microns, simple flotation regents, and no attempts to maximize concentrate grade, recoveries for Au, Ag, Cu and Mo at the Revenue deposit are excellent: 92% Cu, 74% Au, 81%, Mo, 59% Ag.
Table 2 Inferred Mineral Resource Estimate for the Revenue Deposit at Various Au Eq Cutoff Grades
*Gold equivalent (AuEq) is calculated based upon prices of US$1250/oz for gold, US$22.00/oz for silver, US$2.90/lb for copper, and US$10.00/lb for molybdenum and assumes 100% metal recovery. All figures are rounded to reflect the relative accuracy of the estimate and numbers may not add up due to rounding.
** Mineral resources do not demonstrate economic viability, and there is no certainty that these mineral resources will be converted into mineable reserves once economic considerations are applied.