thumb|Closer view of granite outcrop in the Granite Mountains.
The Granite Mountains is a small mountain range in eastern San Bernardino County, California, USA, in the Mojave Desert. The range stretches from Granite Pass to Budweiser Wash. The highest peaks of this mountain range are an unnamed peak, which is in elevation, and Granite Peak, which is in elevation.
The Granite Mountains lies north of Interstate 40 and historic Route 66. The Providence Mountains are adjacent to the Granite Mountains to the northeast. The Bristol Mountains are directly to the west, the Old Woman Mountains are to the southeast, and Pisgah Crater and the Bullion Mountains are to the southwest. The Mountains lie east of the small community of Kelso, northeast of Ludlow, and north of Amboy. This mountain range lies within the Mojave National Preserve, in the National Park Service system.
Geology
The Granite Mountains contains outcrops of rock and sediments ranging in age from Paleozoic to Cenozoic. The Granite Mountains are largely underlain by Mesozoic, Jurassic and Cretaceous, intrusive rocks. At the higher elevations, small roof pendants composed of either Paleozoic dolomite, limestone, or marble occur enclosed within the Mesozoic intrusive rocks. The Cenozoic strata consist of Miocene dikes, late Cenozoic fanglomerates and breccias, and Quaternary alluvium.
Jurassic intrusive suite
The overwhelming majority of the Granite Mountains consists of intrusive rocks in the form of different types of granite, monzonite, and diorite. The exact nomenclature used for each of these types varies from author to author because of differences in the classification system used by each author. These rocks can be divided into Jurassic and Cretaceous intrusive suites. As one time, the oldest of the Jurassic intrusive rocks were tentatively thought to be Triassic in age.
During the latest Proterozoic, Paleozoic, and early Mesozoic, this part of the Mojave Desert was a passive margin along the western edge of the North American craton. Within this passive margin, sedimentary strata accumulated lying unconformably across a deeply eroded surface underlian by Proterozoic gneissic and granitic rocks. These sedimentary rocks accumulated in marine and, less commonly, continental environments along the western edge of the North American craton. The Triassic (?) calc-silicate hornfel xenolith and limestone, dolomite, and marble roof pendants found within the Granite Mountains are all that remain of this once several kilometer-thick blanket of passive margin sedimentary strata that covered this region.
First, the Comanche Mine was first named and patented as mineral claim in 1902. It was known as the El Companche Mine in 1925; as the Comanche Mine in the 1950's; and last known as the Christopher Mine in 1965. When visited by United States Geological Survey geologists in 1982, there were no claims on the property. Although called a mine, it never commercially produce any ore. The Comanche Mine cuts into a roof pendant consisting of Paleozoic dolomitic marble. The marble consists of 41 to 45 percent calcium oxide and 14 to 16 percent magnesium oxide. Locally, the marble contains disseminated copper and iron minerals.