The Johnson Camp Mine copper deposit is a type of copper skarn. The copper skarn at Johnson Camp and collectively in the Cochise mining district is presumably related to the Texas Canyon Quartz Monzonite. Copper skarns generally form in calcareous shales, dolomites, and limestones peripheral or adjacent to the margins of diorite to granite intrusions that range from dikes and sills to large stocks or phases of batholithic intrusions, and frequently are associated with mineralized intrusions. Copper mineralization forms along structurally complex and fractured rocks and convert the calcareous shales and limestones to andradite-rich garnet assemblages near the intrusive body, and to pyroxene and wollastonite rich assemblages at areas more distal to the intrusive that are subject to retrograde alteration with mineral hydrated silicate assemblages that overprint earlier garnet and pyroxene.

Mineralization at Johnson Camp occurs approximately 500 ft northeast of known occurrences of the Texas Canyon Quartz Monzonite intrusion as proximal skarn related to a porphyry copper system. This assumption is supported by the high abundance of garnet-epidote alteration in the mineralized zones, and the characterization of the deposits in numerous historical publications.

The Johnson Camp Mine is located within the Mexican Highland region of the Basin and Range province, which is characterized by fault-bounded mountain ranges, with large intrusions forming the cores of t ........

The Johnson Camp Mine plan f has been developed with the expectation that it will produce leachable copper material and provide cash flow while the Gunnison Copper Project improvements (water treatment plant, new wells) are being constructed. This mine plan targets a small tonnage, higher grade portion of the Burro deposit that is planned to be mined over a 3.5-year period. A contract miner will be selected for executing the mining portion of the Project because of the short duration of the mine plan.

Mining of the deposit is expected to be accomplished with 100-ton haul trucks and front-end loaders. Mining is planned on 20-ft bench heights. The pit configuration is double benched with catch benches every vertical 40 ft.

Pit slope angles are based on observed pit wall angles in the existing Burro pit. A 45-degree inter ramp pit slope angle was chosen for the phase design utilizing 63-degree bench face angles with a 20 ft wide catch bench every 40 ft vertical. The southwest wall of the pit was designed at the angle of the lithology bedding. This results in a 32–40- degree overall pit slope on the southwest wall of the pit. The portion of the pit that mines through existing waste dumps at the top of the NE wall is designed at a 37-degree slope angle with a 50 ft step out at the toe of fill material.

The other parameters used for the phase designs were:
Bench Height: 20 ft (double-benched);
Haul Road Width: 82 ft;
Step out at toe ........

Crushing has been done at Johnson Camp, and the original crushing plant could be reactivated after repairing and upgrading primary and secondary crushers and screens.

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