Idaho's Mineral Resources
Many of the Survey's early publications describe Idaho's natural wealth of mineral resources, both metallic minerals and industrial or non-metallic minerals. The Idaho Bureau of Mines and Geology (IBMG) Pamphlet series includes most of these early works on the geology and ore deposits of specific mining districts. The more recent Idaho Geological Survey (IGS) Staff Report series includes accounts of the history of selected mines or districts, as well as recent field inventories of hazards at inactive mine sites.
Mineral resources are unique, spatially focused, natural geologic concentrations of a particular element or commodity. Idaho mining was an integral part of the state's early settlements. Gold was initially discovered in Idaho in 1860 near Pierce, but the state is best known for its two "world class" mining districts: the fabulous Coeur d'Alene District in northern Idaho and the Western Phosphate Reserve in southeastern Idaho. Over a billion ounces of silver and substantial lead and zinc have been produced in the Coeur d'Alene since 1884, and two deep underground (hard rock) mines are still producing. In southeastern Idaho, near Soda Springs, large open pit mines extract phosphate ore and process it to fertilizer or elemental phosphorus.
Metals currently or recently being mined commercially include silver, lead, copper, and gold. Industrial minerals produced include phosphate rock, sand and gravel, cement, crushed stone, limestone, pumice, dimension stone, zeolites, industrial garnet, gemstones, feldspar, and perlite. Mines and quarries provide important jobs to many rural counties. Urban growth, and infrastructure development and maintenance, has increased demand for materials such as cement, sand, and gravel from suitable aggregate sources. Recreational prospecting for precious and semi-precious metals and gemstones is a popular outdoor pastime in Idaho; gem shops and outfitters can be found throughout the state.
Annual reviews of Idaho mining provide basic information used by the exploration industry, product buyers and suppliers, and regulatory, scientific and environmental organizations, as well as private citizens.
Historically, the Survey's Mines and Prospects database and web application is the standard starting place for anyone looking for minerals in Idaho. Both prospectors and modern exploration geologists also use geologic maps and studies, such as those published by the Idaho Geological Survey and other agencies. Mineral resources are not randomly distributed, rather different types of mineral resources are localized in specific geologic and structural settings.
The Survey's historical information on mines is also being used to guide projects that inventory hazards and environmental concerns at inactive and abandoned mines, many of which are decades old. Over 1,600 properties have been evaluated to date by the Survey's expert personnel in cooperative programs with land management agencies. Knowledge of minerals mined, mining methods and processing techniques, rock types, and fault distributions must be known in detail for risk assessments and development of reclamation plans. However, accurate information on many of the old mines is in danger of being lost without funding for data preservation. The public should not enter or approach old mines due to the risk from many types of hazards.