The Whitehorse Copper Belt is located west of Whitehorse and contains 30+ mines, deposits and showings. By 1900, most of the important deposits had been discovered and the first small ore shipment was made that year. Many of the occurrences in the Copper Belt are skarns. The skarns form on or near the contact between the Whitehorse batholith and the Lewes River group. The Whitehorse batholith is commonly a grey coarse-grained hornblende granite and ranges from quartz monzonite to granodiorite to diorite. The Lewes River group contains numerous different rock types, most importantly of which is the limestone group, which is essential in the formation of skarns in the area.  A small number of occurrences within the Copper Belt are vein and/or replacement and occur within the Whitehorse batholith granite.

The skarn at War Eagle occurs at the within the Lewes River limestone, not far from the contact with the Whitehorse granite batholith. The skarn is banded, with alternating bands of tremolite-garnet and dark feldspar augite rock (10-25 feet wide). The tremolite bands carry bornite and chalcopyrite in grains and small masses and constitute the principal ores. Locally there is also wollastonite, magnetite and molybdenite. Occasionally, the wollastonite and magnetite are replaced by bornite and chalcopyrite. Drilling determined that the ore body extends to a length of 1600 feet and 500 feet in width.

The deposit was mined intermittently beginning in 1900 and ending in 1971 with the majority of production occurring between 1969 and 1971. In total, 1 903 863 tonnes of ore was mined from War Eagle with the average grade being 1.29% Cu with minor Au and Ag.