The Silverquick mercury deposit, approximately 3.8 kilometres northeast of Eldorado Mountain, is within chert pebble conglomerate and interbedded sandstone-shale and chert lithic quartz arenite of the Upper Cretaceous Silverquick Formation (informal usage). The rocks are extremely fractured by joints and faults. The joints are multidirectional and are nearly vertical, spaced a few centimetres to a metre apart. Faults strike northwest, northeast and west, with moderate to steep dips.

Cinnabar is present as disseminated grains, streaks and small lenses within brecciated conglomerate, as smears on slickensided faults and in the mud of gouge seams. Cinnabar is accompanied by quartz, calcite, limonite and clay (dickite).

The area of the Silverquick mine has undergone large scale folding and associated thrust faulting, with subsequent (northwest trending) high angle strike slip faulting. Faulting seems to have taken place both before and after ore deposition. Cinnabar was most likely deposited at relatively shallow depth from low temperature hydrothermal solutions along fractures and faults that greatly enhanced the permeability of the host conglomerate and associated sedimentary rocks.

The mine, producing most of its ore in the early to mid 1960's, yielded about 3180 kilograms of mercury. The mine was operated by Silverquick Development Co. in 1964 and 1965. About 34 kilograms of mercury were produced in 1955.