The Gibellini deposit occurs within organic-rich siliceous mudstone, siltstone, and chert of the Gibellini facies of the Devonian Age Woodruff Formation.

In general, the beds strike north-northwest and dip from 15º to 50º to the west. The black shale unit which hosts the vanadium Mineral Resource is from 175 ft to over 300 ft thick and overlies gray mudstone of the Bisoni facies. The shale has been oxidized to various hues of yellow and orange up to a depth of 100 ft.

Alteration (oxidation) of the rocks is classified as one of three oxide codes: oxidized, transitional, and reduced. Vanadium grade changes across these boundaries. The transitional zone reports the highest average grades and RMP geologists interpreted this zone to have been upgraded by supergene processes.

The Louie Hill deposit lies approximately 500 m south of the Gibellini deposit, being separated from the latter by a prominent drainage. Mineralization at Louie Hill is hosted by organic- rich siliceous mudstone, siltstone, and chert of the Gibellini facies of the Devonian Woodruff Formation and probably represents a dissected piece of the same allochthonous fault wedge containing the Gibellini deposit.

Mineralized beds cropping out on Louie Hill are often contorted and shattered but in general strike in a north–south direction, and dip to the west 0 to 40º.

Rocks underlying the Louie Hill Deposit consist of mudstone, siltstone and fine-grained sandstone probably of Mississippian age (Webb and/or Chainman Formations).

Oxidation of the mineralized rocks has produced light-colored material with local red and yellow bands of concentrated vanadium minerals.

Vanadium mineralization at Gibellini and Louie Hill is hosted in black shale sedimentary rocks. Mineralization is tabular, conformable with bedding, and remarkably continuous in grade and thickness between drill holes.

Alteration of the rocks is limited to oxidation and is classified as one of the three oxide codes: 1 = oxidized, 2 = transitional, and 3 = reduced. Vanadium grades change across these boundaries. The transitional zone reports the highest average grades, the oxide zone reports the next highest average grades, and the reduced zone reports the lowest average grades.

In the oxidized zone, complex vanadium oxides occur in fractures in the sedimentary rocks including metahewettite (CaV6O16·H2O), bokite (KAl3Fe6V26O76·30H2O), schoderite (Al2PO4VO4·8H2O), and metaschoderite (Al2PO4VO4·6- 8H2O). In the reduced sediments, vanadium occurs in organic material (kerogen) made up of fine grained, flaky, and stringy organism fragments less than 15 µm in size (Bohlke et al., 1981).

Other workers found vanadium mineralization to occur within manganese modules (psilomene family) in the shale (Assad and Laguiton, 1973). X-ray diffraction (XRD) mineral identification by SGS Lakefield Research in Ontario, Canada reported the occurrence of the vanadium mineral fernandinite (CaV8O20·H2O) (SGS, 2007). Other minerals reported to occur at Gibellini are marcasite, sphalerite, pyrite, and molybdenite (Desborough et al., 1984).

The PEA mine plan assumes production at 3 Mst/a from two open pits, at Gibellini and Louie Hill.

Open pit mining optimization inputs are based on an open pit bulk mining method. Contract mining is assumed for a contractor using a small equipment fleet. For the pit design, 40° overall slope angles were assumed based on dry conditions.

Five pit phases were developed. Phase I, Phase III and Phase IV are mined from the Gibellini deposit and Phase II and Phase V are mined from the Louie Hill deposit.

The haul roads are designed to accommodate 100 ton haul trucks with a maximum gradient of 10% and an overall width of 85 ft. Access into the final pit bottoms are gained via a section of single lane road 50 ft wide.

Two waste rock storage facilities (WRSF) were designed for a total capacity of 6.8 Mst.

Process design inputs are based on acid heap leaching crushed vanadium ores with dilute sulfuric acid and using a solvent extraction plant to recover the vanadium. Production rates are assumed at 3 Mst leached per year.

Commercial heap leaching and solvent extraction recovery of vanadium mineralization has not been done before; nonetheless, heap leaching and solvent extraction recovery are common technologies in the mining industry. The most notable examples are the multiple copper, nickel, and cobalt heap leach projects that use an acid-leach solution to mobilize the metal followed by recovery in a SX plant, which is then followed by electro-winning. The proposed Gibellini process applies the same acid heap leaching and solvent extraction technology to recover vanadium. However, instead of electrowinning to produce a final product, the process will use an acid strip followed by precipitation to produce a final product.

The processing method envisioned will feed mineralized material from the mine via loader to a hopper that feeds the screening and crushing plant. The screen will send any material greater than a third-inch and less than four inches in size to the cone crusher (plus four-inch material will be sent to stockpile for further treating).

The crushed material will recycle to the screen feed belt, thus crushing in closed circuit. The minus half-inch mineralized material will be fed to the agglomerator where sulfuric acid, flocculent (agglomeration aid) and water will be added to achieve proper agglomeration. The agglomerated mineralized material will be transported to a stacker on the leach pad, which will stack the mineralized material to a height of 15 ft. Once the material is stacked and sufficient material accumulated to distribute sprinklers onto the leached material, solution will be added to the leach heap at a rate of 0.0025 gallons per minute per square foot. The solution will be collected in a pond and this pregnant leach solution (PLS) will be sent to the process building for metal recovery.

The PLS will be treated with iron to convert all of the vanadium in solution from the vanadate (VO3-) form to the vandyl (VO+2) form, which will be preferentially loaded onto the organic phase in the extraction phase of treatment. Solvent extraction mixers–settlers will be used to recover the vanadium onto the organic phase and to produce a vanadium depleted aqueous solution (raffinate). The raffinate will then be returned to the leach pad to continue to leach the vanadium remaining in the heap material. The loaded organic phase from the extraction will then be contacted in a separate set of mixer–settlers (the strip circuit). Here the vanadium will be pulled from the organic phase into the new aqueous phase. The stripped organic will then be returned to the extraction circuit where it will be re- loaded with vanadium. The stripped vanadium solution will then be oxidized to vanadate with sodium chlorate and ammonia will be used to form ammonium metavanadate (AMV). Sulfuric acid will be added to the AMV and a precipitate will be formed. This precipitate will be settled in a thickener and the thickened material will be sent to a centrifuge. The thickener overflow will be recycled back to the strip circuit where it will be loaded with vanadium again.

Approximately 130 million pounds of V2O5 will be produced from Gibellini leaching operations at an average recovery of 62% (oxide: 60%, transition: 70% and reduced: 52%).