SILVERTON GOLD-SILVER PROJECT, NEVADA, USA
Orogen executed a binding and exclusive term sheet (“Exclusive Agreement”) with Galileo Resources plc, (“Galileo”), in June 2016, pursuant to which Orogen has the right to earn-in to a 51% interest in Galileo’s Silverton Gold-Silver property (“Silverton” or the “Property”) in Nevada, USA by way of exploration expenditure of US$400,000 (the “First Expenditure”) within 18 months and thereafter the possibility to spend an additional US$1,500,000 (the “Second Expenditure”) within 30 months to earn-in a further 24% interest, in total 75%, in the Property (the “Farm-out”).
Galileo will have the right to participate pro rata after the First Expenditure; should it exercise this right it would retain a 49% equity interest in Silverton (as opposed to being diluted down to 25%).
- Galileo has granted Orogen the right to earn an initial 51% interest in the Silverton project over the 6km² claim area through exploration spend of US$400,000 over 18 months
- Orogen may earn an additional 24% interest in the project through a further exploration spend of US$1.5 million over a subsequent 30 month period
- Previous bedrock and drill sampling outlined an area >0.5g/t Au measuring 1km x 0.5km
- Assay intervals reported by Newcrest (2003) up to 7.62m@ 2.29g/t Au and 10.67m @ 1.0g/t, including 1.52m @ 5.01g/t Au (non-Code compliant)
- Historic silver and gold production from district
- Drilling by Orogen in late 2016 returned gold intervals assaying up to 0.2g/t Au over 71.63m in the vicinity of the Silverton Fault
The Property is located northeast of Tonopah in the central Pancake Range. The Silverton claim block comprises 72 lode claims staked by Newcrest in March 2002.
Small-scale mining operated in the area from 1930 to 1937 and in 1953. Total production for the district is <100,000 oz. silver, <2,000 oz. gold and <1 ton of antimony. Over the last three decades multiple companies including Olympic Mining, Westgold, Newmont and Pittston have explored the property for gold and silver. Work completed comprised geochemical sampling, fluid inclusion studies, mapping, geophysics and drilling (~45 pre-Newcrest holes).
Since 2002 Newcrest has taken over 1,000 rock chip samples and drilled 42,983ft in 29 RC (reverse circulation) drill holes.
The Silverton district occurs at the eastern margin of a caldera complex dated at 34Ma. Both high and low angle faults and fault breccias related to caldera rim tectonics are observed on the property. Rocks consist of Palaeozoic dolomite/limestone detachment blocks surrounded and underlain by Tertiary rhyolite tuffs. Rhyolite dikes have also been mapped along caldera ring fractures and north trending faults.
Tuffs around the Palaeozoic rocks are locally bleached and argillized (kaolinite – clay). Both units are silicified along faults, generally as jasperoid bodies up to 9m wide. Jasperoid also forms flat-lying replacement horizons within volcanic beds. Additional silicification includes stockwork silica veining and chalcedony +- stibnite-pyrite veins. One to two percent disseminated pyrite and minor stibnite occurs in tuffaceous rocks over a 6km2 area. Other mineralization includes barite, gypsum, and alunite. Ore-grade gold values are generally associated with veins, strongly veined limestone, and argillized tuff along mineralized structures and adjacent to jasperoid. Most jasperoid bodies themselves contain only low-level gold.
The property contains a >100ppb Au rock chip anomaly measuring 2.5km x 3km. Au, Ag, As, and Hg mineralization are broadly coincident. Within the anomaly, the most significant of three main zones is a NNE trending area (Silverton Fault Zone) >0.5g/t Au measuring 1km x 0.5km and centered on a 100m wide silicified contact between rhyolite to the east and carbonate rocks to the west.
Old vertical drilling on the southern end of the Silverton Fault Zone returned several intervals of 5ft @ 1-5g/t Au and 100-600g/t Ag. The best Newcrest intercept is 25 feet @ 2.3g/t Au in rhyolite tuff.
No metallurgical testing has been carried out on rocks from the Silverton district and potential recoveries are unknown. However, gold occurrence could be fine grained, micron sized, as none is observed in pan concentrates.
The geologic environment is similar to disseminated and bonanza epithermal gold mineralisation at the Round Mountain mine Nevada. The Silverton property and area of volcanic rocks to the west are prospective for exposed and concealed oxide and sulphide tuff- and intrusion -hosted disseminated and associated and/or carbonate-hosted bonanza style epithermal gold mineralisation. In the relatively untested area along the 1km Silverton Fault Zone, with a 0.1-1.5g/t Au anomaly at surface, the potential exists for bonanza gold silver ‘feeder’ veins. In addition, low-grade bulk tonnage disseminated gold can also occur in the rhyolite porphyry intrusions, similar to e.g. Kori Kollo in Bolivia
Orogen’s initial reverse circulation drilling programme in late 2016 was focussed on testing the potential of the Silverton Fault for the postulated deeper feeder systems. Holes were angled at 60 to 70 degrees towards the west and northwest across the steeply east-dipping fault system over a 600m strike length from north to south. The holes generally confirmed earlier results, with low-grade gold occurring in a package of iron-stained and pyrite-bearing felsitic tuff and quartzite within the hanging-wall sequence above the fault structure. Three of the four holes aimed at the fault zone intersected gold mineralisation, including a wide interval in OS-2, however the intercepts were not enhanced compared to the shallower historic holes. The intervals are detailed in the table below:
|Silverton Project, Nevada – Au assay results, Orogen Gold RC drilling, October 2016|
|Hole No||Depth from (m)||Depth to (m)||Interval (m)||Au g/t|
Operating in Nevada
Nevada is considered one of the best places in the world to explore and develop a gold deposit:
- One of the best gold-endowed regions in the world
- In 2014, Nevada produced almost 5Moz gold, representing 73% of all US production
- Several of the world’s major gold miners operate there, including Newmont Mining, Goldcorp and Barrick Gold
- Low sovereign risk
- Good infrastructure and access
- State administration supportive of mining
- Well established exploration/mining/environmental permitting system
- Considerable exploration and mining expertise and ready access to services