INSIDE UPDATE: Pioneer Resources (ASX: PIO) is moving closer to starting Australia’s first caesium mine at the company’s 100 per cent-held Pioneer Dome project in the Eastern Goldfields of Western Australia.
Pioneer Resources Pioneer Dome lithium-caesium-tantalum (LCT) project includes the Sinclair Zone caesium deposit, which currently hosts a Mineral Resource Estimate of 10,500 tonnes of the caesium ore, pollucite, with a grade of 17.1 per cent caesium oxide (Cs2O).
Pollucite is a rare mineral of caesium that forms only in extremely differentiated zones of rare-metal lithium-caesium-tantalum pegmatite systems.
It is found in commercial quantities at the Bikita Mine in Zimbabwe and the Tanco Mine in Canada, where it is mined principally for use in the manufacture of Caesium Formate, a high-density fluid used in high-temperature/high-pressure oil and gas drilling.
Caesium Formate provides several well documented benefits including, minimal damage to the hydrocarbon-bearing formation resulting in higher production rates, where it acts as a lubricant, is non-corrosive and is considered an environmentally-friendly benign chemical when compared to alternatives. Caesium in principal commercial usage is the non-radioactive isotope.
Pioneer recently completed a program of diamond-drilling at Pioneer Dome to infill five sections with the strongest caesium mineralisation – in the form of the mineral pollucite – in preparation for final open pit mine design work.
Each of the key sections returned pollucite intersections in line with earlier modelling
Caesium (pollucite) intersections included:
11.15 metres at 17.43 per cent Cs2O from 38.2m;
5.70m at 29.61 per cent Cs2O from 37.7m;
2.68m at 27.11 per cent Cs2O from 40.82m and 7.18m at 16.04 per cent Cs2O from 47.88m;
7.45m at 16.58 per cent Cs2O from 43.6m; and
4.30m at 20.89 per cent Cs2O from 43.5m.
The program of pre-mine drilling at the Sinclair Zone caesium deposit consisted a total of 20 drill holes, producing 1,333.29m of core.
Of the 20 holes drilled, 15 holes targeted caesium or lithium mineralisation.
Four holes were completed adjacent to the proposed pit walls to provide geotechnical information, and one hole became blocked and was abandoned.
Most holes also intersected potassium (microcline).
Armed with the lithium and caesium results, Pioneer’s geological consultants from the Mitchell River Group are revising the Mineral Resource Estimate for caesium.
Potassium (microcline) samples, which require specialised processing, are currently being analysed.
The open pit design and confirmation economic study are on track to be concluded by the end of May 2018.
In addition to the targeted caesium (pollucite) mineralisation, Pioneer has encountered broad zones of a range of other alkali-metal minerals, including lithium (petalite and lepidolite) and potassium (microcline) within the Sinclair Pegmatite.
On the basis that the Board determines to proceed with mining, as the microcline, petalite and lepidolite will be ‘mined through’ to access the pollucite, the company will stockpile these minerals, and is advancing commercial opportunity discussions for each with third parties.
“The Sinclair deposit is proving to be an exciting opportunity for the company as it moves towards its first mining operation,” Pioneer Resources managing director David Crook said.
“This round of drilling confirmed the continuity of the pollucite mineralisation, significantly de-risking the project from an ore supply perspective.”
Pioneer recently completed a drilling program with its Joint Venture partner, TSXV-listed International Lithium Corp. at the Mavis Lake lithium project in the province of Ontario, Canada.
The program returned a standout intersection of:
55.25m at 1.04 per cent lithium oxide from 82.75m.
All nine holes intersected spodumene mineralisation, usually in the form of multiple wide zones of pegmatite.
“The Joint Venture considers the 2018 drilling program to be definitive for the project, as all nine holes intersected significant lithium mineralisation, including the most heavily mineralised hole drilled to date,” Crook said.
Pioneer Resources Ltd. (ASX: PIO)
… The Short Story
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West Perth WA 6005
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Craig McGown, David Crook, Wayne Spilsbury, Allan Trench