The Mesquite Mining District lies beneath alluvial pediment deposits at the base of the Chocolate Mountains along the San Andreas fault system. Gold mineralization occurs within complex assemblage of regional scale fault blocks that comprise distinct rock units and host the more than 3 million ounces of gold that have been produced at Mesquite since its discovery circa 1940.  Currently remaining mineral resources at Mesquite contain an estimated 4.1 million ounces of gold.  

Gold mineralization at Mesquite was emplaced during mid-Tertiary time (26-38 Ma) within a complex system of faults and fractures that have been superimposed upon an older sequence of Jurassic age gneisses and granitic intrusive. The local stratigraphic sequence is, from bottom to top: mafic, hornblende biotite, and biotite gneiss overlain by Bay Horse Quartzite and Muscovite Schist. These units have been crosscut by a number of quartz, feldspar, biotite and muscovite rich granite sills, plutons and dikes. The gneiss units are present in a shallowly dipping stratigraphic sequence, offset by numerous high and low angle faults. This package is overlain by up to 400 feet of Tertiary lithified silts, sands, and gravels and unconsolidated Quaternary gravels.

There are three main structural components that serve as the principal controls to gold mineralization at the Mesquite Mine. Northwest trending structures appear to have the greatest control on gold distribution, while younger northeast trending cross-faults offset mineralization in a stair step fashion. East-west striking near vertical and northwest striking low angle structures are also seen on the property. The system is bounded by structures sub-parallel to the San Andreas Fault system. Mid-Tertiary age deposition of gold was within an epithermal environment along faults and fractures, and the deposit was subsequently oxidized down to approximately 150 meters (500 ft) below current surface topography. Gold at Mesquite occurs as both submicron disseminated and coarse gold, with flakes of visible ‘flour gold’ occurring along fault zones throughout the mine area.