High-Grade Zinc-Silver-Gold Drill Intersections Extend Mineralisation at Red Mountain
The first two drill holes of the 2018 program to test the down plunge extension of mineralisation at both the Discovery lens and the Fosters lens at the Dry Creek deposit have returned exceptional zinc, lead, silver and gold grades:
o 4.7m @ 19.5% zinc, 7.8% lead, 466g/t silver, 6.9g/t gold and 1.5% copper for 49.7% ZnEq(see Note below) (DC18-79), including 1.6m @ 18.5g/t Au.
o 4.3m @ 4.8% zinc, 2.3% lead, 1,435g/t silver, 2.2g/t gold and 0.5% copper for 43.2% ZnEq(see Note below) (DC18-77).
- The Discovery lens hole (DC18-79) intersection is the best result of all the historic holes drilled into the Discovery lens.
- This drilling extends the high-grade Fosters and Discovery Lenses and highlights the exceptional growth potential as the mineralisation remains open.
The diamond drilling results are part of White Rock's maiden drill campaign at the Red Mountain project. Drilling is now targeting extensions of the two existing deposits, Dry Creek and West Tundra, which already have a Resource base of 16.7Mt at 8.9% ZnEq(see Note below) including a high-grade component of 9.1Mt @ 12.9% ZnEq(see Note below) (refer ASX announcement 26 April 2017 regarding the maiden Mineral Resource).
MD & CEO Matt Gill said "This drilling represents a significant extension to the Dry Creek deposit and notably down dip at both the Fosters and Discovery lenses. These first two extension drill holes highlight the upside potential for a significant expansion to the Resource at Dry Creek, both in terms of grade and size. Dry Creek is an exciting VMS deposit as it shows great variation in thickness that has the potential to rapidly add to the Resource. These current drill holes also highlight the potential for significant high-grade gold and silver with individual assays up to 25g/t Au and 1,795g/t Ag (or more than 50 ounces of silver per tonne in the old measure). In addition, we are continuing to see more copper as we explore to the east, supporting an early interpretation that the VMS system may be improving towards the east and at depth, where improving zinc grades could also be expected. And all this before we have really got our teeth into testing some of the best of the more than 30 already identified regional exploration targets within our 143km2 land package."
The drill program continues to test extensions of the Discovery lens with a further two drill holes completed (assays awaited) and another drill hole underway. The long-section and cross-section presented in Figures 2 & 3 (see link below) illustrate the upside potential for down-plunge mineralisation extensions. The Dry Creek deposit shows typical pinching and swelling of mineralisation as is often encountered in other VMS deposits, underlining the upside potential for down-plunge and along strike Resource expansion through drill testing.
In addition to drilling at the Discovery lens, results for the first drill hole testing the down plunge extension of mineralisation at the Fosters lens of the Dry Creek deposit have also been received. DC18-77 intersected two zones of semi-massive sulphide mineralisation. The lower zone returned exceptional silver mineralisation.
This drill program is being supported by applying on-ground geophysics (CSAMT), along with surface mapping and rock and soil sampling analysis. Some of the drill holes have also been prepared for follow-up geophysical testing using down-hole EM.
Results for DC18-77 and DC18-79 are summarised in Table 1 (see link below).
About Red Mountain (as more fully set out in the ASX Announcement dated 15 February 2016)
- The Red Mountain Project is located in central Alaska, 100km south of Fairbanks, in the Bonnifield Mining District. The tenement package comprises 230 mining claims over a total area of 143km2.
- The Red Mountain Project contains polymetallic VMS mineralisation rich in zinc, silver and lead, with potential for significant gold and copper.
- Mineralisation occurs from surface and is open along strike and down-dip.
- White Rock used historical drilling to determine a maiden JORC 2012 Mineral Resource estimate for the Dry Creek and West Tundra Flats deposit (ASX Announcement 26th April 2017). The Inferred Mineral Resource contains an impressive base metal and precious metal content with 678,000t zinc, 286,000t lead, 53.5 million ounces silver and 352,000 ounces gold.
- Good preliminary metallurgical recoveries of >90% zinc, >75% lead, >80% gold, >70% silver and >70% copper.
- Previous drilling highlights (ASX Announcement 15th February 2016) include:
o 4.6m @ 23.5% Zn, 531g/t Ag, 8.5% Pb, 1.5g/t Au & 1.0% Cu from 6.1m
o 5.5m @ 25.9% Zn, 346g/t Ag, 11.7% Pb, 2.5g/t Au & 0.9% Cu from 69.5m
o 7.1m @ 15.1% Zn, 334g/t Ag, 6.8% Pb, 0.9g/t Au & 0.3% Cu from39.1m
West Tundra Flats
o 1.3m @ 21.0% Zn, 796g/t Ag,9.2% Pb, 10.2g/t Au & 0.6% Cu from 58.6m
o 3.0m @ 7.3% Zn, 796g/t Ag, 4.3% Pb, 1.1g/t Au & 0.2% Cu from160.9m
o 1.7m @ 11.4% Zn, 372g/t Ag, 6.0% Pb, 1.7g/t Au & 0.2% Cu from 104.3m
- VMS deposits typically occur in clusters ("VMS camps"). Deposit sizes within camps typically follow a log normal distribution, and deposits within camps typically occur at regular spacing. The known deposits at Dry Creek and West Tundra Flats provide valuable information with which to vector and target additional new deposits within the Red Mountain camp.
- Interpretation of the geologic setting indicates conditions that enhance the prospectivity for gold-rich mineralisation within the VMS system at Red Mountain. Gold mineralisation is usually found at the top of VMS base metal deposits or adjacent in the overlying sediments. Gold bearing host rocks are commonly not enriched in base metals and consequently often missed during early exploration sampling. This provides an exciting opportunity for potential further discoveries at Red Mountain.
- White Rock sees significant discovery potential, given the lack of modern day exploration at Red Mountain. This is further enhanced by the very nature of VMS clustering in camps, and the potentially large areas over which these can occur.
Note: ZnEq = Zinc equivalent grades are estimated using long-term broker consensus estimates compiled by RFC Ambrian as at 20 March 2017 adjusted for recoveries from historical metallurgical test work and calculated with the formula: ZnEq =100 x [(Zn% x 2,206.7 x 0.9) + (Pb% x 1,922 x 0.75) + (Cu% x 6,274 x 0.70) + (Ag g/t x (19.68/31.1035) x 0.70) + (Au g/t x (1,227/31.1035) x 0.80)] / (2,206.7 x 0.9). White Rock is of the opinion that all elements included in the metal equivalent calculation have reasonable potential to be recovered and sold.
To view tables and figures, please visit:
About White Rock Minerals Ltd
White Rock Minerals Ltd (ASX:WRM) is an Australian listed minerals exploration and development company with projects located in northern NSW (gold and silver) and central Alaska (zinc, silver, lead and gold). The White Rock vision is to explore and develop both precious and base metal projects.
White Rock's cornerstone asset is the Mt Carrington epithermal gold-silver project in northern NSW. The Mt Carrington project has great leverage to the Australian gold and silver prices with a positive scoping study providing a path towards feasibility studies and development in the near term.
White Rock is also exploring the Red Mountain project in Alaska. Red Mountain is a globally significant advanced VMS project with high grade zinc and silver in two deposits. White Rock is exploring for additional high grade deposits that will enhance the projects leverage to an upturn in the fortunes of zinc and silver.
White Rock Minerals Ltd