Earlier this year, the US State of Nevada overtook Western Australia as the world’s No.1 mining jurisdiction, according to the Fraser Institute’s latest annual survey of mining companies.
But just down the road, the State of Arizona has also been attracting significant interest from ASX-listed exploration companies such as Riedel Resources, Eagle Mountain Mining and Patriot Lithium.
It makes for a vastly different field of battle than the area’s gunslinging days of old. But just like in Western Australia, there is plenty happening in what is traditionally known as the “wild west”.
Arizona has consistently registered in the Fraser Institute’s top-10 mining jurisdictions in the past five years – lodging in seventh place in the latest survey. It rose as high as second in 2020 and was nominated as the fifth-best last year.
And there is a rich regional history to consider as a backdrop to its more modern mining and exploration activities.
Arizona initially attracted interest for its silver vein deposits, with mining kicking off in the late 1800s. The silver boom led to a rush of prospectors and miners flocking to the area and was influential in the establishment of several towns in the State, including the infamous Tombstone – which played host to the bloody Gunfight at the O.K. Corral way back in 1881.
But more recently, silver has been produced as a byproduct in copper mining, which has become one of the State’s major industries.
Copper mining is big business and has even attracted two of Australia’s big guns to work together on the Resolution Copper project. The operation is a joint venture (JV) between Rio Tinto (55 per cent) and BHP (45 per cent) and represents one of the most significant untapped copper deposits, with an estimated resource of 1.787 billion tonnes at an average grade of 1.5 per cent. The ore deposit lies some 2134m below surface, with the JV waiting on permit approvals.
Eagle Mountain Mining is also on the search for copper in Arizona with its Oracle Ridge and Silver Mountain projects. Silver Mountain covers about 40 square kilometres and comprises three main prospects known as Pacific Horizon, Scarlett and Red Mule, which are all wholly-owned by Eagle Mountain.
However, the company’s primary focus this year has been at Oracle Ridge, where it unearthed whopping grades of up to 25.5 per cent copper, 1935 grams per tonne silver and 15.2g/t gold in a 0.6m hit from a diamond drilling campaign in March.
Eagle Mountain is currently preparing a mineral resource upgrade following further solid drill results after revealing an initial resource of 16.5 million tonnes at 1.45 per cent copper, 15.1g/t silver and 0.19g/t gold for a total of 240,000 tonnes of copper, more than eight million ounces of silver and in excess of 100,000 ounces of gold in October last year.
However, copper and silver are not the only commodities ASX-listed companies are searching for in Arizona.
Patriot Lithium holds its Wickenburg lithium project about 70km north-west of Phoenix, where exploration at the start of this year identified three pegmatites that it says show potential for spodumene mineralisation. The lithium explorer officially received the green light for a maiden drill campaign at the operation in June after its wholly-owned subsidiary, New Energy Metals was granted approval from the Bureau of Land Management.
The company has planned a 14-hole diamond drill campaign to cover 1015m and it will be separated into two phases. The first phase of the program will consist of seven holes for up to 420m. Based on the analysis of its initial visual results, an additional seven holes will be sunk for about 595m immediately afterwards.
Management says the campaign will test the outcropping Dove West spodumene pegmatite at the historic Dove pegmatite mine and is expected to provide a better understanding of the lithium mineralisation in the shallow subsurface.
Selective spodumene samples from the Dove pegmatite mine at Dove West returned some solid results, including grades of up to 5.88 per cent lithium oxide. Rock-chip samples from LCT pegmatites along the Dove West, Dove East and Mammoth trends have returned many anomalous results greater than 0.01 per cent lithium oxide.
Management says that due to the intense surface weathering and leaching of the rocks, the results are considered anomalous. A peak lithium-in-rock-chip value of 1.35 per cent lithium oxide has been returned from the lower cut at the historic Dove pegmatite mine. Soil sampling has identified zones of significant lithium, caesium and tantalum at the Dove, Mammoth and Vulture pegmatites and some new target areas.
Riedel Resources is another serious ASX-listed player aiming to strike it rich in Arizona. The company is aiming to deliver a maiden resource for its Kingman gold project after some impressive hits from its recent drill work.
Kingman sits about 90 minutes south of Las Vegas, in an area mined for high-grade gold and silver from the 1880s until the onset of World War II. However, it has seen only limited exploration and drilling since – in the 1990s and then three years ago when 11 diamond drill holes intersected high-grade zones of gold, silver and lead from shallow depths.
Riedel picked up the project through an earn-in agreement with Flagstaff USA in October, 2020. It quickly got to work by drilling 104 reverse-circulation (RC) holes in 2021 at the Tintic, Merrimac, Arizona Magma and Jim’s historic mines.
In February, the explorer hit a 0.24m intersection going a significant 130g/t gold, 732g/t silver and 28 per cent lead from just 21m. The headline hit was within a broader 0.76m running at an equally impressive 52.8g/t gold and 261g/t silver from 20.4m. The results complement a recently-reported 0.37m section grading 122.6g/t from 67.4m at the historic gold play.
Riedel says Tintic is the biggest gold zone in the Kingman operation and has been defined as 700m long by up to 250m wide, with most mineralisation within 60m of surface. Previous drilling returned impressive shallow results including a 3.8m hit at a glittering 98.9g/t gold and 151g/t silver from just 20.6m.
In January, the company confirmed shallow, high-grade gold at Kingman after sifting through its first batch of assays from a 23-hole diamond drilling program completed late last year. Highlights from the project’s first set of assays boasted several notable results including 1m at 47.9g/t gold, 266g/t silver and 10.5 per cent lead from 17.5m.
The feature 1m result sat inside a longer 5.5m intercept going 12.4g/t gold, 105g/t silver and 3.9 per cent lead from 16.8m. It was joined by another 1m parcel running 14.3g/t gold, 222g/t silver and 14.6 per cent lead from a depth just shy of 19m.
After scoring a bundle of high-grade gold hits in its first outing with a diamond drill rig, management believes the mineralised zone at Tintic is flat-lying, shallow, potentially very-high grade and up to 600m long – characteristics which could promote a solid open-pit mining operation.
Other companies with significant projects based in Arizona include Gold 50, which saw gun smoke billowing around its share price in July after hitting significant gallium mineralisation in a maiden drill campaign at its Golconda project. The explorer says it found the precious metal in 11 of the 14 holes of its latest campaign, including a 109m intersection going 40.5g/t gallium from 129m. Other headline results included 241m grading 20g/t gallium from surface, 308m running 28.6g/t from surface and 271m at 23.8g/t, again from surface and containing 70m going 34.2g/t from 93m.
New World Resources is also preparing for production at its Antler copper project in Arizona. The operation boasts a mineral resource of 11.4 million tonnes grading 2 per cent copper, 6.7 per cent zinc 22.6g/t silver and 0.36g/t gold. Just last week, the company declared it was set kick off further exploration drilling, with all work to date limited to just 600m of strike.
So, while Nevada may appear to be an attractive proposition for those willing to take a punt, it would be worthwhile to consider the historic and current value of the impressive mineral discoveries being developed in the neighbouring State of Arizona.
Sitting not too far from Nevada’s renowned gambling hub of Las Vegas, those already plying their trade in Arizona will be hoping their educated punt pays off in spades and that a major mining jackpot awaits.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By Michael Philipps
