Gold in Mariposa County
Sierra Sun Times file photo

Read the Full Report

May 13, 2019 - The California Geological Survey provides an annual summary of the state’s mineral production exclusive of oil, gas, geothermal, and coal. The summary provides information on non-fuel mineral production, mining events, new permitting, exploration, and mining legislation. To provide information in a timely manner, preliminary production estimates are given. Final production data for California’s 2017 Non-Fuel Mineral Production will be available in the 2019 summary.

California Non-Fuel Mineral Production 2017 - California ranked fifth among the states in non-fuel mineral production, accounting for approximately 4.7% of the United States total. There were 1,042 active mines in the state, and of those, 663 reported the production of non-fuel minerals during 2017. The total market value of production was $3.6 billion. In terms of value, the top three non-fuel minerals produced in 2017 were construction sand and gravel, portland cement, and crushed stone.

Excerpts from the report:

Based on preliminary data for 2017 from the U.S. Geological Survey (USGS) National Minerals Information Center, California ranked fifth – after Nevada, Arizona, Texas, and Alaska – in the value of non-fuel mineral production (USGS, 2018). The market value of non-fuel mineral production for California was $3.6 billion – approximately 4.7 percent of the nation’s total (USGS, 2018).

The USGS provided the California Geological Survey (CGS) with production statistics for 23 non-fuel mineral commodities based on their surveys of the mineral industry in 2017. California led the nation in the production of diatomite and construction sand and gravel and was the only U.S. producer of boron and rare earth elements. Texas was the only state to produce more portland cement than California in 2017 (USGS, 2018). Other mineral commodities produced in the state are listed in Table 1.

Based on data from the California Department of Conservation’s Division of Mine Reclamation (DMR), there were about 1,042 active mines in California during 2017, and of those, 663 reported the production of non-fuel minerals. Approximately 5,500 people were employed at these mines and their processing facilities (California Employment Development Department, 2018).

METALS

Metals made up the remaining eight percent of the value of non-fuel minerals produced in California. Gold dominated California’s metals market in 2017 – totaling over 98 percent of the value of the state’s metals production. The quantity and value of 2017 gold production increased 56 percent from 2016.

The state’s largest gold producer was the Western Mesquite Mine in Imperial County – approximately 168,800 troy ounces for the year (New Gold, Inc., 2018). The Soledad Mountain Mine in Kern County produced 46,041 troy ounces during 2017, its first full year of commercial production (Golden Queen Mining Co. Ltd., 2017).

In addition to the above-mentioned lode mines, placer gold was recovered as a byproduct from many sand and gravel mines in the northern and central parts of the state. California also has several small lode mines that sporadically produce gold, including specimens for the collector market.

Silver is a byproduct of gold production in California and in 2017 made up less than two percent of the state’s total metal production by value. The Soledad Mountain Mine was the source of nearly all the silver – over 239,000 ounces – produced during the year (Golden Queen Mining Co. Ltd., 2017).

Iron ore was mined almost exclusively in San Bernardino County and used in the production of portland cement. Because of this primary end-use in its unrefined oxide form, iron ore is considered an industrial mineral, despite its metallic mineralogy.
Source: CA. DOC