Ares Strategic Mining's September 2021 technical report for the Lost Sheep fluorspar property in Juab County, Utah, designs crushing, two-stage grinding and up to nine cleaner stages for 80% fluorite recovery.
The Technical Report on the Lost Sheep Fluorspar Property, Juab County, Utah, U.S.A., was prepared by P&E Mining Consultants and others for Ares Strategic Mining Inc. with an effective date of September 17, 2021. The report cautions that Ares has not completed a feasibility study or a mineral reserve or resource estimate at the Lost Sheep mine, and that it is proceeding on the basis of past production and internal projections, with a correspondingly higher risk of failure. The flotation plant is designed for a nominal 500 t/d of feed averaging 40% CaF2, to make high-purity 97% fluorite (acid-spar) at a minimum total fluorite recovery of 80%. A separate process recovers lump CaF2.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Report effective date | September 17, 2021 | Not applicable | P&E Mining Consultants for Ares Strategic Mining Inc. |
| Nominal throughput | 500 | t/d | 198,400 t/a in the design criteria |
| Feed grade | 40 | % CaF2 | Average |
| Product grade | Above 97 | % CaF2 | Acid-spar; metspar if not achieved |
| Fluorite recovery | 80 | % minimum | Total |
| Crushing | Jaw and cone crushers, 9 mm screen | Not applicable | 12 h/d, 7 d/week at 42 t/h |
| Primary grind | P80 75 | µm | 70% solids, 250% circulating load |
| Regrind | P80 50 | µm | Closed circuit |
| Cleaner stages | Up to nine | Not applicable | Product can be drawn from earlier cleaners |
| Flotation pulp density | 25 | % solids | Not applicable |
| Product moisture | Below 0.5 | % | Rotary dryer, bagged |
| Tailings moisture | Below 8 | % | Dried and trucked back to backfill pits |
Overview
The preliminary testwork set the grind target, conditioning times, number of cleaner stages and reagent additions needed to reach acid-spar grade. The tested route was a grind to P80 75 µm, seven minutes of multi-stage high-intensity conditioning, rougher flotation and one cleaner, then a regrind to P80 50 µm, another seven minutes of conditioning and seven to nine further cleaning stages. Reagents are soda ash for pH, OMC-1234 or oleic acid as the fluorite collector, Tan-XS to depress calcite, and Sep-X50 or sodium silicate to depress silica.
Key Process Stages
Ore receipt and crushing. Trucks deliver 500 t/d to a ROM pad holding three to four days of feed, about 2,000 t, with truck scales measuring tonnage in and out. A vibrating grizzly feeds a jaw crusher. Crushed material is screened at 9 mm, and oversize goes through a cone crusher and back to the screen. Undersize goes to a 500 t fine ore bin, which buffers the plant across the 12-hour crushing shifts. Crushing runs 12 hours a day, seven days a week, to limit disruption to the local community.
Primary grinding and desliming. A ball mill at 70% solids, with a cyclone and 250% circulating load, grinds to P80 75 µm. A desliming cyclone can remove fines and clays, which harm flotation, and send them straight to the tailings thickener.
Rougher and scavenger flotation. After high-intensity conditioning, the slurry goes to rougher flotation. Rougher tails pass to a scavenger module, whose concentrate returns to the rougher feed. Scavenger tails are thickened and filtered.
Regrind and cleaning. Rougher concentrate passes the first cleaner and a closed-circuit regrind mill to P80 50 µm, then secondary conditioning and up to eight further cleaner modules to bring the fluorite to over 97%. Product can be drawn from an earlier cleaner once 97% is reached, because more cleaning only loses fluorite to tails.
Product dewatering. Acid-spar concentrate is thickened, vacuum disc filtered and rotary dried to below 0.5% moisture, then packed in super sacks or 50 kg paper sacks. A second thickener collects metspar-grade concentrate if acid-spar grade is not met, so the plant can keep a revenue stream.
Tailings. Tailings are thickened, vacuum filtered and dried to below 8% moisture, then trucked back to the mine to backfill open pits. Thickener overflow and filtrate are reclaimed for the primary mill.
Additional Interesting Data and Summary
The report gives the number of cleaner stages in slightly different ways: seven to nine stages in the testwork route, nine cleaner stages in the scaled-up design, and up to eight cleaner modules after the regrind in the process description. This article reports each figure as stated.
In summary, the 2021 Lost Sheep design is a small acid-spar flotation plant that relies on a fine regrind and many cleaning stages to lift 40% CaF2 feed to 97%, with dry-stacked tailings returned to the pits, built without a mineral reserve on the strength of past production.
Key Processes
- Jaw and cone crushing with 9 mm screening
- Ball milling to P80 75 µm with optional desliming
- High-intensity reagent conditioning
- Rougher and scavenger fluorite flotation
- Regrind to P80 50 µm and multi-stage cleaning
- Thickening, vacuum filtration and rotary drying of acid-spar
- Optional metspar product line
- Filtered, dried tailings for pit backfill
Source: Technical Report on the Lost Sheep Fluorspar Property, Juab County, Utah, U.S.A., for Ares Strategic Mining Inc., effective date September 17, 2021.
Earlier report summaries
Earlier versions of this profile, based on older technical reports, are retained below for source traceability. Dates and figures reflect each report’s own effective date and are superseded by the current information above.
Technical Report on the Lost Sheep Property, Utah
This technical report describes the Lost Sheep Property, a fluorite mining property in Juab County, Utah, including its historical production, proposed exploration programme, and processing infrastructure.
Report context
This NI 43-101 technical report was prepared for Lithium Energy Products, a British Columbia company trading on the Venture Exchange as LEP.V, and is dated 30 June 2019. The Lost Sheep Property, totalling 5.856 km², is located in the Spor Mountain area, Juab County, Utah, approximately 214 km south-west of Salt Lake City. The report covers regional and local geology, mineralisation, exploration history, and proposes an exploration programme and budget for fluorite exploration and development on the property.
Processing route
Delta warehouse and bagging plant
The property acquisition includes a nine-acre plant site by a Union Pacific railroad siding in Delta, Juab County, Utah. On Sugar Factory Row, a three-port warehouse with a processing plant for the mining operation is located in the SW.NW. and NW.SW. section 6, T.17S., R.6W., SLBM, Delta. The property consists of parcel D3864-3-1 (registered in the names of joint tenants Michael and Gail Provstgaard [2/3] and Steven Long [1/3]) and parcels D3864-3, D3864-4 and D3864-7 registered in the names of Michael Provstgaard and Gail Provstgaard (deceased). On privately held land, these four parcels total 8.84 acres (3.5 hectares). Taxes on these parcels were current and paid to 2017. The assessed valuation of the parcels totals $20,853 in land and $77,950 in buildings. In 2016, taxes on all these parcels and improvements totalled $1,217.32.
Sited at the three-port warehouse is a small bagging plant in which 50 pound sacks of beneficiated fluorite are prepared for shipping. The Delta warehouse contains a final sorting system and bagging equipment, with bags approximately 50 lb. The author's 2019 visit verified the same set-up.
On-site facilities and equipment
The following on-site facilities and equipment related to the Lost Sheep mine property were listed. All or some may be included in the final acquisition agreement. The author visited the warehouse but did not inspect all of the items and cannot verify the condition or suitability of any of the following:
- Powder magazine
- Trailer
- Hoist building
- Tool shed
- Head frame
- Bus (storage)
- Cabin
- Shipping container
- Dried product storage building
- Air compressor/generator building
- Drying shed/equipment storage building
- Mobile crushing, screening and drying equipment
- Welded pipe gate
- Wire rope gate
- Horse corral
- Jaw crusher and ore bin (not used recently)
- Ore bin
Proposed exploration and development
A programme of exploration and development is recommended, including advancing development of the Little Giant Pipe at the Lost Sheep Mine, by surface drilling and underground development with continuation of historic adit work. Exploration should cover a re-assessment of the geology on all the properties as there was a lack of systematic work over the past 60 years. Geological mapping and prospecting are recommended, with follow-up shallow drilling of prospects be they fluorite showings or deeper diamond drilling of potentially buried targets. A budget of US$669,000 is proposed for future, near-term exploration, drilling, drive and adit development.
Historical mining and processing
Fluorite mining dates back to 1943, with over 350,000 tons of ore shipped from 29 deposits, with the vast majority from the Lost Sheep Mine (260,000 tons). The Lost Sheep Mine is the only remaining fluorite producer in the District. Mined material was characteristically described as high grade, with low impurities, and was favoured by steel mills for these reasons. Over 90% of extraction across Spor Mountain came from mineralised brecciated pipes located within or adjacent to faults and shear zones, and often with a spatial relationship to Tertiary rhyolitic to rhyodacitic intrusions and breccias.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Property area | 5.856 km² | Design |
| Total mineral claims | 67 | Design |
| Historic fluorite ore shipped (entire district) | Over 350,000 tons | Historical operating data |
| Historic ore shipped from Lost Sheep Mine | 260,000 tons | Historical operating data |
| Original claims purchase price | US$1 million | Design |
| Purchase price payment terms | 9% of average monthly sales from fluorspar materials | Design |
| Proposed exploration budget | US$669,000 | Proposed design |
| Number of historic mining deposits in district | 29 | Historical operating data |
| Delta warehouse property area | 8.84 acres (3.5 hectares) | Design |
| Delta warehouse assessed land value | $20,853 | Design |
| Delta warehouse assessed buildings value | $77,950 | Design |
| Delta warehouse annual tax (2016) | $1,217.32 | Design |
| Bag size at bagging plant | 50 lb | Design |
Project website: https://www.aresmining.com/lost-sheep-mine
Technical qualifications
This report was prepared according to the specifications outlined in Form 43-101F1 for the Standards of Disclosure for Minerals Deposits, National Instrument 43-101. Any mineral resources that were sourced and reviewed by the author are for historic purposes only and do not meet the requirements of NI 43-101. The author has not independently verified ownership or mineral title beyond information that has been provided by the Issuer. The property description presented in this report is not intended to represent a legal or any other opinion as to title or current ownership.
Source: Technical Report on the Lost Sheep Property, Utah, dated 30 June 2019, prepared for Lithium Energy Products, Sections 1, 2, 4, 13, 16, 17, 18, 26.
