Beneath the Nevada soil lies a story waiting to be unearthed a story of exploration and extraction centered around the Sunday Mine. The Sunday Mine Complex is not just a single mine. It is a group of five mines including the Sunday Mine.
The Sunday Mine Complex sits in western San Miguel County, Colorado. It includes the Carnation mine, the Saint Jude mine, the West Sunday mine, and the Topaz mine. This complex was actively mined from 2007 to 2009. Imagine the bustling activity during those years.
The Sunday Mine Complex covers approximately 3800 acres. These acres are on public lands. Twenty of these claims are subject to a royalty on all ore produced. Each mine has its own permit. Currently, they are all in Temporary Cessation.
To resume operations, permits need updates. Ablation onsite needs inclusion. A mine water treatment plant must be installed. Necessary permits for water treatment are also essential.
Geologically, uranium-vanadium mineralization dominates the Sunday Mine Complex. Fluvial sandstone beds host this mineralization. These beds belong to the upper Salt Wash Member of the Jurassic Morrison Formation. Minor production comes from conglomeratic sandstones. These are part of the lower Brushy Basin Member of the Morrison Formation.
Beds generally strike northwest-southeast. They dip southwest. Faults near Big Gypsum Valley create exceptions. The deposit model aligns with Sandstone Uranium Tabular subtype. This is according to USGS Bulletin 1693.
Mineralogy includes uraninite and coffinite. Pyrite appears in organic-rich horizons. Chlorite is also common. The deposits are stratabound. Tabular uranium intimately mixes with pore-filling humin. This forms tabular lenses within reduced sandstone. Wood and carbonaceous material are replaced.
Humic acid mineralizing fluids leach iron. This leaves relict TiO2 minerals. Oxidized iron minerals are updip. Reduced iron minerals are downdip from the redox interface. Permeability is an ore control. Humic or carbonaceous material concentrates uranium.
One feature is the colloquially-termed red front. This marks the change from red oxidized to gray unoxidized sandstone. This happens in the mineralized horizons.
Historically, various sized mining companies owned or controlled these deposits. Some mines belonged to mill owners. Others had owner-lessees who shipped ore to regional mills. The destination depended on toll contracts. It also depended on the mineralogy of the uranium and host rocks.
Conventional milling extracts uranium. Trucks deliver ore. The ore is crushed. Sulfuric acid is often the leaching agent. Alkaline solutions can also be used.
The Sunday Mine stands as a testament to resource extraction. It also highlights the geological processes that concentrate valuable minerals. The mine shows our enduring quest to extract resources from the earth.