"Mining History" Map Layers

This grouping of map layers are part of a Land Matters project to provide researchers with an historical perspective on mining of the public lands. Although several these map layers are available on Land Matters maps addressing other subjects they are provided here so researchers can directly compare past mining activity with current mining claims status.


"Topo Mineral Features" Map Layer


This new map layer is the beginnings of an effort by the USGS to incorporate the Mineral Resources Data System with known verifiable mining features from historic topo maps.

This is a huge and ongoing effort that may help bring the MRDS mines data into a more useable form. Look for changes and additions to these map layers to eventually become the go to source for locational mines and mineral data in the U.S.
Until that process is complete we will be presenting the MRDS mines layer as a companion map layer. Clever researchers will use both layers together to get advanced information on historical mineral resources that are location specific.

These data are part of a larger USGS project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. Mine and prospect-related symbols, such as those used to represent prospect pits, mines, adits, dumps, tailings, etc., hereafter referred to as “mine” symbols or features, are currently being digitized on a state-by-state basis from the 7.5-minute (1:24, 000-scale) and the 15-minute (1:48, 000 and 1:62,500-scale) archive of the USGS Historical Topographic Maps Collection, or acquired from available databases (California and Nevada, 1:24,000-scale only). Compilation of these features is the first phase in capturing accurate locations and general information about features related to mineral resource exploration and extraction across the U.S. To date, the compilation of 500,000-plus point and polygon mine symbols from approximately 67,000 maps of 22 states (AR, AZ, CA, CO, ID, IA, KS, LA, MN, MO, MT, ND, NE, NM, NV, OK, OR, SD, TX, UT, WA and WY) has been completed.

Symbols used on this map layer

 Mine   Mine Shaft   Adit   Trench   Pit   Air Shaft   Millsite


Symbol Notes

"MRDS" Map Layer


This map layer displays the records previously provided in the Mineral Resource Data System (MRDS) of USGS and the Mineral Availability System/Mineral Industry Locator System (MAS/MILS) originated in the U.S. Bureau of Mines, which is now part of USGS.

The MRDS is a large and complex relational database developed over several decades by hundreds of researchers and reporters. While database records describe mineral resources worldwide, the compilation of information was intended to cover the United States completely, and its coverage of resources in other countries is incomplete.

The content of MRDS records was drawn from reports previously published or made available to USGS researchers. Some of those original source materials are no longer available.

The information contained in MRDS was intended to reflect the reports used as sources and is current only as of the date of those source reports. Consequently MRDS does not reflect up-to-date changes to the operating status of mines, ownership, land status, production figures and estimates of reserves and resources, or the nature, size, and extent of workings. Information on the geological characteristics of the mineral resource are likely to remain correct, but aspects involving human activity are likely to be out of date.

Collected over many decades, this information is highly variable in quality. Currency of individual records is variable as well, so it is likely that some information will be found to be out of date. This is a subject of continuing refinement by the USGS and its cooperators.

Collected and reported by numerous diverse people, the descriptions provided are not highly consistent in structure or terminology. Recent revision of the MRDS database has begun to address this issue, and the present database digest contains fields chosen for their general consistency, though much work remains to be done. The database is generally sparse; many records have no information for a given field. A few fields required for proper processing are complete throughout.

Positional information is highly variable. In the best cases this information was provided by plotting the location on a 7.5 minute topographic map, however many records were located on the basis of published reports containing imprecise or scant information on the specific geographic location. Approximately 4000 records have no reliable geographic coordinates, although about 114 of those have other locational information systematic enough to warrant placement within the controlled vocabulary used to select data for analysis on the web.

Symbols used on this map layer

Mineral Resource Data System Items


Symbol Notes

"Mineral Patents" Map Layer


This map layer has been derived by Land Matters from the General Land Office (GLO) database of nearly 6 million Land Patents. It is unique to Land Matters.

Mineral Patents are displayed on a per section basis on the map. Turning on the PLSS "Special Surveys" map layer in combination with the "Land Manager" map layer will give you a better visual reference of the data being displayed.

Using the "i" tool to query this layer for information will provide you with a link to the GLO copy of the actual Patent as issued. To download all the pages of the Patent select the multiple page PDF symbol at the bottom right of the Patent display window.

Many Patent images have not been processed yet but you can still get a raw copy of the Patent image by selecting the "Related Documents" Tab and then clicking on "CDI" from the link list to the left of the "Related Documents" window and choosing the "Image" symbol next to the Mineral Patent listing you are interested in. The Mineral Survey Plats are available in a similiar manner by choosing "Surveys" from the left link list instead of "CDI".

Symbols used on this map layer

Mineral Patents


"Historical Mining Claims" Map Layer


Historical Mining Claims is a graphic representation of mining claims density by section in the United States from 1976 to 2011. A year by year and claim type graph is available on each section.

The darker the red color on the map the higher the historical density of mining claims in that Section.

Symbols used on this map layer

Mining Claims Historical Density


Symbol Notes