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next few years kept the project's recovery schedule rocking on its heels as ownership shares, financing, production strategies, potential customers, and market econom- ics shifted and changed—eventually stabi- lizing and leading to a concerted effort to develop a viable mining, processing and marketing approach for the mine. The cur- rent owners returned it to production in 2010, first supplying crushed ore to mar- ket, and now, with the completion of a new concentrator, providing high-quality mag- netite concentrates to offshore buyers while preparing for a move into the North American market for high-density media. The mine is owned and managed by CML Metals Corp. (CML)—formerly known as Palladon Iron Corp., a subsidiary of Palladon Ventures that was set up in 2005 to develop the Iron Mountain project. Palladon Ventures currently holds an approximate 19% share of CML—WUCC dropped out of the project in 2006—and a fund managed by New York City-based Luxor Capital Group owns most of the remaining interest in CML. Situated 16 miles west of Cedar City, the property encompasses more than 6,000 acres of private lands and patented and unpatented mining claims on public lands. All orebodies are located on private land. A project economic assessment conduct- ed by SRK Consulting in 2009 reported NI- 43-101 compliant resources of 36.6 million metric tons (mt), containing about 45.3% iron. Of that, 28.4 million mt was located in the closely adjacent Comstock and Mountain Lion deposits and the rest was in the form of stockpiled lower-grade ore (about 33.9% Fe content). Currently, the company reports reserves of about 30 million mt; another 150 million mt are classified as "non- reserve mineralization," having been identi- fied and drilled but not included in the com- pany's near-term development plan. The Comstock and Mountain Lion (CML) deposits have been the primary source of ore throughout the mine's existence. The Rex and A/B deposits to the southwest of the Comstock/Mountain Lion pit are areas of interest that have been surveyed both by aeromagnetic methods and drilling and offer future production opportunities. The SRK study described the property's iron mineralization as magnetite and lesser amounts of hematite occurring in the Homestake Limestone member of the Carmel Formation. Mineralization is found in lenticular, stratiform bodies and can be up to 3,900 ft long by 2,000 ft wide with thicknesses ranging from a few feet to approximately 250 ft. These bodies are found in roof pendants suspended in the Iron Mountain laccolith as well as along the flanks of the laccolith. Post mineral fault- ing has offset the mineralization with dis- placements of up to approximately 300 ft. Although the Comstock and Mountain Lion deposits are physically separate from each other, they are close together and both are mined within a single pit. Gilbert Development Corp., a Utah-based earth- works, construction, and mining company, handles drilling, blasting, blending, and haulage from the pit and from ore stock- piles under contract to CML Metals; CML Metals owns the mine, concentrator and related facilities. Gilbert's association with the mine goes back several decades, hav- ing been the mining contractor for two pre- vious owners—USX, from 1985–87; and Geneva Steel, from 1987–95. In fact, sev- eral former Gilbert employees now com- prise the core management of CML Metals—including President and CEO Dale Gilbert, COO Sam Paioletti and Mine Manager Penn Leavitt. The Iron Mountain mine lies in a semi- arid zone that is actually only a couple dozen miles beyond the northern fringes of the Mojave Desert, but at an altitude that brings frequent, sometimes heavy, winter snowfall. According to Leavitt, it's not un- common for mining activities to be briefly interrupted during the winter months when some units of the production fleet are assigned, by necessity, to snow removal duty. Leavitt said the miners are used to operating in these conditions and are quick to bring the mine back into operation after big snowstorms. The overall strip ratio in the active min- ing area is very low (0.48, waste to ore) and future production will most likely access ore deeper in the pit without need of addi- tional prestripping. The mining method is straightforward: Ore blocks are identified, rotary drilled and blasted, assigned to a blending plan, flagged, and mucked. The broken ore, distinguishable from lighter- colored waste by its dark gray color, is loaded by a Komatsu WA900 wheel loader or PC2000 hydraulic excavator into a fleet of Cat 785 trucks for a short haul to the plant's primary crusher—a horizontal shaft impactor that reduces incoming ore to 6- in. minus size prior to delivery to a SAG mill. Concurrently, stockpiled "lean" ore from past operations is loaded by another Komatsu WA900 into a hopper and deliv- ered by conveyor to an intermediate stock- pile, from which ore is drawn for blending with ore from the pit prior to crushing. The mine maintains a large stockpile down- stream from the crusher, serving as both a surge pile during normal operations and an extended source of plant feed when mining operations are interrupted. SEPTEMBER 2014 • E&MJ; 37 www.e-mj.com M A G N E T I T E M I N I N G One of the mine's two Delkor thickeners dewaters magnetite concentrate and another handles tailings. In the back- ground, lean ore is crushed, then stockpiled for blending with higher-grade ore from the pit.