Drill core (cut in half) inside diamond drill core bit
Annual Data and Maps
The Lands and Minerals Division compiles data related to private exploratory borings, or drill holes, in Minnesota. Provided here are data and maps pertaining to exploratory borings in Minnesota since 1987.
If you have questions please contact:Minnesota Department of Natural Resources
tel. 651-296-6157
tel. 888-646-6367
Did you know?
- Mineral exploration drill holes make up less than 1% of all drilling in the state.
View slide » - Drill holes are sealed according to state law.
Visit Department of Health to learn more » - It costs an estimated $100,000 to drill 1,000 feet of drill core ($100 per/ft). This is an estimate and includes costs such as: geologist, site selection, geophysics, salaries, and drilling costs.
- Only 2.6% of all state leased parcels had exploration drilling completed on them according to an analysis of exploration drilling on state metallic minerals leases over 50 years.
View analysis » - The average size of a drill pad is 70'x70' which is approximately 1/10 of an acre in extent. At this size it would take 400 exploratory drill pad sites to fill a 40 acre footprint.
Learn more
Mineral Exploration Process »
Mineral Exploration Regulations »
State Oversight of Metallic Mineral Exploration Activities »
Exploration by Year
- 2023
- Exploration drilling in 2023
- Download map of exploration drill hole locations completed in 2023
Table: Exploration Drilling in 2023| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Talon Nickel (USA) LLC | 60 | Nickel | Aitkin |
| Teck American Inc. | 15 | Cu+Ni+PGM+Co | St. Louis |
| NewRange Copper Nickel LLC | 18 | Cu, Ni | St, Louis |
| North Star Manganese | 32 | Mn | Crow Wing |
| ^Hibbing Taconite Co. | 2 | Iron | St. Louis |
| ^Cleveland Cliffs MN Land Development Co. | 39 | Iron | St. Louis |
| ^United States Steel Co. - Minntac | 8 | Iron | St. Louis |
| Total | 174 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM+Co indicates Copper, Nickel, Platinum Group Metals, and Cobalt.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2022
- Exploration drilling in 2022
- Download map of exploration drill hole locations completed in 2022
Table: Exploration Drilling in 2022| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Talon Nickel (USA) LLC | 68 | Nickel | Aitkin |
| Teck American Inc. | 10 | Cu+Ni+PGM+Co | St. Louis |
| Vermilion Gold LLC | 18 | Gold | Itasca, St. Louis |
| ^Arcelor Mittal Minorca Mine Inc. | 9 | Iron | St. Louis |
| ^Glacier Park Iron Ore | 3 | Iron | St. Louis |
| ^United States Steel Co. - Minntac | 16 | Iron | St. Louis |
| Total | 124 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM+Co indicates Copper, Nickel, Platinum Group Metals, and Cobalt.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2021
- Exploration drilling in 2021
- Download map of exploration drill hole locations completed in 2021
Table: Exploration Drilling in 2021| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Talon Nickel (USA) LLC | 108 | Nickel | Aitkin |
| Teck American Inc. | 6 | Cu+Ni+PGM+Co | St. Louis |
| Vermilion Gold LLC | 29 | Gold | Itasca, St. Louis |
| ^Cleveland Cliffs MN Land Development Co. | 1 | Iron | St. Louis |
| ^Hibbing Taconite Co. | 2 | Iron | St. Louis |
| Total | 146 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM+Co indicates Copper, Nickel, Platinum Group Metals, and Cobalt.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2020
- Exploration drilling in 2020
- Download map of exploration drill hole locations completed in 2020
Table: Exploration Drilling in 2020| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Encampment Minerals, Inc. | 2 | Cu+Ni+PGM | St. Louis |
| Talon Nickel (USA) LLC | 19** | Nickel | Aitkin |
| ^Arcelor Mittal Minorca Mine Inc. | 4 | Iron | St. Louis |
| Total | 25 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals
**Count includes seven wedged holes, also known as daughter holes, child holes, branch holes, or wedges. A wedged hole is drilled when the drill bit is purposely deflected out the side of a parent (existing) hole.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2019
- Exploration drilling in 2019
- Download map of exploration drill hole locations completed in 2019
Table: Exploration Drilling in 2019| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| AngloGold Ashanti Minnesota | 55 | Gold | Itasca and St. Louis |
| Encampment Minerals, Inc. | 2 | Cu+Ni+PGM | St. Louis |
| Vermillion Gold | 6 | Gold | Itasca |
| ^Hibbing Taconite Company/Cleveland Cliffs | 4 | Iron | St. Louis |
| Total | 67 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2018
- Exploration drilling in 2018
- Download map of exploration drill hole locations completed in 2018
Table: Exploration Drilling in 2018| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| AngloGold Ashanti Minnesota | 99 | Gold | Itasca and St. Louis |
| Kennecott Exploration Co. | 4** | Cu+Ni | Aitkin |
| Polymet Mining Inc. | 18 | Cu+Ni+PGM | St. Louis |
| ^ArcelorMittal Minorca Mine Inc. | 26 | Iron | St. Louis |
| ^Cleveland Cliffs Minnesota Land Development LLC | 6 | Iron | Itasca |
| ^Hibbing Taconite Company/Cleveland Cliffs | 3 | Iron | St. Louis |
| Total | 156 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals
**Count includes three wedged holes, also known as daughter holes, child holes, branch holes, or wedges. A wedged hole is drilled when the drill bit is purposely deflected out the side of a parent (existing) hole.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2017
- Exploration drilling in 2017
- Download map of exploration drill hole locations completed in 2017
Table: Exploration Drilling in 2017| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| AngloGold Ashanti Minnesota | 29 | Gold | Koochiching |
| Kennecott Exploration Co. | 12 | Cu+Ni+PGM | Aitkin |
| Vermillion Gold LLC | 14 | Gold | St. Louis |
| Total | 55 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals - 2016
- Exploration drilling in 2016
- Download map of exploration drill hole locations completed in 2016
Table: Exploration Drilling in 2016| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Twin Metals Minnesota LLC | 1 | Cu+Ni+PGM | Lake |
| Kennecott Exploration Co. | 30** | Ni+Cu | Aitkin |
| Total | 31 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
**Count includes eight wedged holes, also known as daughter holes, child holes, branch holes, or wedges, and one extension. A wedged hole is drilled when the drill bit is purposely deflected out the side of a parent (existing) hole.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2015
- Exploration drilling in 2015
- Download map of exploration drill hole locations completed in 2015
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
The map and table do not show 8 drill holes completed for iron ore in the biwabik iron formation.Table: Exploration Drilling in 2015| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Encampment Minerals, Inc. | 9 | Cu+Ni+PGM | St. Louis and Lake |
| Kennecott Exploration Co. | 17 | Cu+Ni | Aitkin and Carlton |
| Vermillion Gold LLC | 7 | Gold | St. Louis |
| ^ArcelorMittal | 8 | Iron | Itasca |
| Total | 41 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2014
- Exploration drilling in 2014
- Download map of exploration drill hole locations completed in 2014
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
The map and table do not show 40 drill holes completed for iron ore in the biwabik iron formation and 17 drill holes completed by MnDOT for highway projects.Table: Exploration Drilling in 2014| Exploration Company or Agency | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| DMC USA LLC | 5 | Cu+Ni+PGM | St. Louis and Lake |
| Kennecott Exploration Co. | 12 | Cu+Ni | Aitkin |
| Twin Metals Minnesota | 9 | Cu+Ni+PGM | Lake |
| ^Hibbing Taconite Co. | 17 | Iron | St. Louis |
| ^Mag Mining LLC | 12 | Iron | Itasca |
| ^US Steel Corp. | 11 | Iron | Itasca |
| MnDOT | 17 | Iron - Condemnation drilling; highway 53 relocation | St. Louis |
| Total | 83 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2013
- Exploration drilling in 2013
- Download map of exploration drill hole locations completed in 2013
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
The map and table do not show 10 drill holes drilled by US Steel for iron ore in the biwabik iron formation.Table: Exploration Drilling in 2013| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| DMC USA LLC | 24 | Cu+Ni+PGM | Lake |
| Encampment Minerals | 1 | Cu+Ni+PGM | St. Louis |
| Kennecott Exploration Co. | 39** | Cu+Ni+PGM | Aitkin |
| Minerals Processing Corp. | 4 | Cu+Ni+PGM | Aitkin |
| Teck American Inc. | 72 | Cu+Ni+PGM | St. Louis |
| Twin Metals Minnesota | 104*** | Cu+Ni+PGM | St. Louis and Lake |
| ^US Steel | 10 | Iron | St. Louis |
| Total | 254 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
**Count includes one wedged hole, also known as daughter holes, child holes, branch holes, or wedges. A wedged hole is drilled when the drill bit is purposely deflected out the side of a parent (existing) hole.
***Count includes five wedged holes.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2012
- Exploration drilling in 2012
- Download map of exploration drill hole locations completed in 2012
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
The map and table do not show 11 drill holes drilled by Hibbing Taconite and 1 drill hole drilled by ArcelorMittal in 2012.Table: Exploration Drilling in 2012| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Cooperative Minerals Resources | 4 | Manganese | Crow Wing |
| DMC USA LLC | 27 | Cu+Ni+PGM | Lake |
| Encampment Minerals | 5 | Cu+Ni+PGM | St. Louis |
| HTX Minerals | 1 | Cu+Ni+PGM | Aitkin |
| Kennecott Exploration Co. | 29 | Cu+Ni+PGM | Aitkin |
| Twin Metals Minnesota | 131 | Cu+Ni+PGM | St. Louis and Lake |
| ^Hibbing Taconite | 11 | Iron | St. Louis |
| ^ArcelorMittal | 1 | Iron | St. Louis |
| Total | 209 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2011
- Exploration drilling in 2011
- Download map of exploration drill hole locations completed in 2011
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
The map and table do not show 10 drill holes drilled by United States Steel in 2011.Table: Exploration Drilling in 2011| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| Cardero Resources | 11 | Iron and Titanium | St. Louis |
| Cooperative Mineral Resources | 4 | Manganese | Crow Wing |
| Duluth Metals | 8 | Cu+Ni+PGM | Lake |
| Encampment Minerals | 7 | Cu+Ni+PGM | St. Louis |
| Kennecott Exploration Co. | 6 | Cu+Ni+PGM | Aitkin and Carlton |
| MMG USA | 2 | Cu+Ni+PGM | Brown and Blue Earth |
| Prime Meridian Resources | 3 | Cu+Ni+PGM | Koochiching |
| Twin Metals Minnesota | 133 | Cu+Ni+PGM | St. Louis and Lake |
| ^United States Steel | 10 | Iron | St. Louis |
| Western Metals | 4 | Cu+Ni+PGM | Lyon and Renville |
| Total | 188 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
^Iron exploration when it is done outside of a mining area described in a permit to mine. - 2005-2010
- Exploration drilling between 2005-2010
- Download map of exploration drill hole locations between 2005-2010.
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
Table: Exploration Drilling 2005-2010| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| ACME-OCHS Brick and Stone | 19 | Kaolin Clay | Brown, Redwood, and Renville |
| Cardero Resources | 36 | Iron and Titanium | St. Louis |
| Duluth Metals/Twin Metals | 205 | Cu+Ni+PGM | Lake |
| Encampment Minerals | 37 | Cu+Ni+PGM | Lake and St. Louis |
| Franconia Minerals | 50 | Cu+Ni+PGM | Lake and St. Louis |
| Kennecott Exploration Co. | 124 | Cu+Ni+PGM, Zinc, Lead | Aitkin, Carlton, Kanabec, Mille Lacs, Morrison, and Stearns |
| Lehmann Exploration | 14 | Gold | Itasca and St. Louis |
| ^Mesabi Nugget | 3 | Iron | St. Louis |
| Minerals Processing Corp. | 11 | Cu+Ni+PGM, Zinc, Lead | Aitkin and Carlton |
| PolyMet Mining Corp. | 234 | Cu+Ni+PGM | St. Louis |
| Teck American Inc. | 137 | Cu+Ni+PGM | St. Louis |
| ^United States Steel Corp. | 49 | Iron | Itasca and St. Louis |
| Western Metals LLC | 5 | Cu+Ni+PGM | Lyon |
| WMC | 5 | Cu+Ni+PGM | Renville and Yellow Medicine |
| Total | 929 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.
^Iron exploration when it is done outside of a mining area described in a permit to mine.Table: Exploration Drilling 2005-2010 By Year| Exploration Company | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | Total |
|---|
| ACME-OCHS Brick and Stone | | | | 16 | 3 | | 19 |
| Cardero Resources | | | | | | 36 | 36 |
| Duluth Metals/Twin Metals | | 10 | 72 | 72 | 2 | 49 | 205 |
| Encampment Minerals | | | | 24 | 13 | | 37 |
| Franconia Minerals | 4 | 7 | 16 | 12 | | 11 | 50 |
| Kennecott Exploration Co. | 19 | | 15 | 52 | 17 | 21 | 124 |
| Lehmann Exploration | | | | | 4 | 10 | 14 |
| ^Mesabi Nugget | | | | 3 | | | 3 |
| Minerals Processing Corp. | | | | | | | 11 |
| PolyMet Mining Corp. | 107 | | 61 | | | 66 | 234 |
| Teck American Inc. | | | 22 | 115 | | | 137 |
| ^United States Steel Corp. | | | 8 | 28 | 7 | 6 | 49 |
| Western Metals LLC | | | | | | 5 | 5 |
| WMC | 5 | | | | | | 5 |
| Total | 135 | 17 | 194 | 322 | 46 | 215 | 929 |
- 1999-2004
- Exploration drilling between 1999-2004
- Download map of exploration drill hole locations completed between 1999-2004
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
Table: Exploration Drilling 1999-2004| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| BHP Minerals International Inc. | 3 | Iron | St. Louis |
| Encampment Minerals | 6 | Cu+Ni+PGM | Lake |
| Kennecott Exploration Co. | 25 | Cu+Ni+PGM, Zinc, Lead | Aitkin, Carlton, Morrison, and Stearns |
| Lehmann Exploration | 28 | Cu+Ni+PGM | Lake and St. Louis |
| Rendrag Inc. | 1 | Cu+Ni+PGM | St. Louis |
| Wallbridge America LTD | 3 | Cu+Ni+PGM | Lake |
| WMC | 1 | Cu+Ni+PGM | Renville |
| Total | 67 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.Table: Exploration Drilling 1999-2004 By Year| Exploration Company | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | Total |
|---|
| BHP Minerals International Inc. | 2 | 1 | | | | | 3 |
| Encampment Minerals | | | | | | 6 | 6 |
| Kennecott Exploration Co. | | | | 3 | 11 | 11 | 25 |
| Lehmann Exploration | 2 | 12 | 7 | 6 | 1 | | 28 |
| Rendrag Inc. | 1 | | | | | | 1 |
| Wallbridge America LTD | 1 | 1 | 1 | | | | 3 |
| WMC | 5 | | | | | 1 | 1 |
| Total | 6 | 14 | 8 | 9 | 12 | 18 | 67 |
- 1993-1998
- Exploration drilling between 1993-1998
- Download map of exploration drill hole locations completed between 1993-1998
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
Table: Exploration Drilling 1993-1998| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| American Shield | 5 | Cu+Ni+PGM | St. Louis |
| Cominco | 16 | Cu+Ni+PGM, Zinc, Lead | Aitkin, Carlton, Lake of the Woods, St. Louis, and Wilkin |
| Exmin Corporation | 8 | Diamond | Beltrami, Koochiching, Marshall, and Roseau |
| Great Lakes Exploration | 1 | Cu+Ni+PGM | Carlton |
| Lehmann | 2 | Cu+Ni+PGM | St. Louis |
| Phelps Dodge | 3 | Cu+Ni+PGM | Roseau |
| Total | 35 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group MetalsTable: Exploration Drilling 1993-1998 By Year| Exploration Company | 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | Total |
|---|
| American Shield | | 4 | | | 1 | | 5 |
| Cominco | | 1 | 9 | 5 | | 1 | 16 |
| Exmin Corporation | 2 | | 1 | | 5 | | 8 |
| Great Lakes Exploration | 1 | | | | | | 1 |
| Lehmann | | | 1 | | | 1 | 2 |
| Phelps Dodge | 3 | | | | | | 3 |
| Total | 6 | 5 | 11 | 5 | 6 | 2 | 35 |
- 1987-1992
- Exploration drilling between 1987-1992
- Download map of exploration drill hole locations completed between 1993-1998
- Associated table with drill hole information; County, Township, Range, Section, Company, Drill Hole Name, Depth (if known), and Date Drilled.
- Additional information for individual boreholes can be found using DNR's Drill Core Library web map.
Table: Exploration Drilling 1987-1992| Exploration Company | Number of
Drill Holes | Target
Commodity | Counties |
|---|
| American Shield | 1 | Cu+Ni+PGM | St. Louis |
| Bear Creek | 1 | Cu+Ni+PGM | St. Louis |
| BHP Minerals International Inc. | 5 | Gold | Koochiching and St. Louis |
| Coca Mines | 19 | Gold | St. Louis |
| Cominco | 1 | Base Metals | Norman |
| Exmin Corporation | 30 | Diamond | Beltrami, Benton, Chippewa, Clay, Clearwater, Koochiching, Lac Qui Parle, Marshall, Mille Lacs, Morrison, Redwood, Renville, St. Louis, Stearns, Stevens, and Wilkin |
| Exxon | 2 | Cu+Ni+PGM | Roseau and Beltrami |
| FMC | 2 | Gold | St. Louis |
| Great Lakes Exploration | 5 | Cu+Ni+PGM, Zinc, Lead | Carlton |
| Hibbing Taconite Land Co. | 31 | Iron | St. Louis |
| INCO | 12 | Cu+Ni+PGM | St. Louis |
| Kennecott Exploration | 1 | Cu+Ni+PGM | St. Louis |
| Kerr-McGee Corp. | 8 | Gold | Koochiching and St. Louis |
| Lehmann | 14 | Cu+Ni+PGM and Gold | Itasca (Gold), Lake, and St. Louis |
| Meridian L&M Co. | 18 | Gold | Itasca |
| Newmont Exploration Ltd. | 134 | Gold | Beltrami, Itasca, Koochiching, Marshall, Norman, Roseau, and St. Louis |
| Noranda Exploration | 27 | Gold | Beltrami, Itasca, Norman, and St. Louis |
| Normin Mining Co. | 27 | Cu+Ni+PGM | Itasca and Koochiching |
| Phelps Dodge | 2 | Cu+Ni+PGM | Lake of the Woods |
| Resource Exploration | 10 | Cu+Ni+PGM | St. Louis |
| Rhude and Fryberger Inc. | 11 | Gold | St. Louis |
| Total | 361 | | |
Notes
The Target Commodity is an interpretation for this summary table.
Cu+Ni+PGM indicates Copper, Nickel, and Platinum Group Metals.Table: Exploration Drilling 1987-1992 By Year| Exploration Company | 1987 | 1988 | 1989 | 1990 | 1991 | 1992 | Total |
|---|
| American Shield | | | | | 1 | | 1 |
| Bear Creek | | 1 | | | | | 1 |
| BHP Minerals International Inc. | | 1 | 3 | 1 | | | 5 |
| Coca Mines | | 19 | | | | | 19 |
| Cominco | | | | | 1 | | 1 |
| Exmin Corporation | 4 | 7 | 4 | 11 | 4 | | 30 |
| Exxon | 1 | 1 | | | | | 2 |
| FMC | | | 2 | | | | 2 |
| Great Lakes Exploration | | 5 | | | | | 5 |
| Hibbing Taconite Land Co. | | | | | 31 | | 31 |
| INCO | | | 12 | | | | 12 |
| Kennecott Exploration | | | | 1 | | | 1 |
| Kerr-McGee Corp. | | 6 | 2 | | | | 8 |
| Lehmann | 5 | 2 | 3 | 4 | | | 14 |
| Meridian L&M Co. | 12 | 6 | | | | | 18 |
| Newmont Exploration Ltd. | 9 | 19 | 20 | 9 | 72 | 5 | 134 |
| Noranda Exploration | 3 | 5 | 1 | 10 | 8 | | 27 |
| Normin Mining Co. | 4 | 6 | 16 | 1 | | | 27 |
| Phelps Dodge | | | | | | 2 | 2 |
| Resource Exploration | | 6 | | 4 | | | 10 |
| Rhude and Fryberger Inc. | 7 | | 4 | | | | 11 |
| Total | 45 | 84 | 67 | 41 | 117 | 7 | 361 |
1987-2023 Chart
Number of private exploratory borings, or drill holes, drilled in Minnesota (1987-2023)
Chart displaying number of exploration drill holes per year (1987-2023).
Click to enlarge
