Region
United States
1,112
Colorado
38
California
33
Alaska
30
Pennsylvania
28
Idaho
24
Florida
23
Nevada
17
New Jersey
17
Tennessee
15
Arizona
13
Wyoming
13
West (U.S.)
12
Utah
11
Illinois
10
Texas
10
Japan
9
Montana
9
New Mexico
9
Southern States
9
Washington (State)
9
Maryland
8
Mississippi
8
China
7
New York (State)
7
Kansas
6
Kentucky
6
Michigan
6
Northwest, Pacific
6
Soviet Union
6
Arkansas
5
Korea (South)
5
Missouri
5
Oklahoma
5
South Carolina
5
Tongass National Forest
5
Virginia
5
Coeur d'Alene Mining District
4
Massachusetts
4
Mexico
4
Montgomery County
4
North America
4
Ohio
4
Oregon
4
Outer space
4
Piceance Creek Watershed
4
Puerto Rico
4
Rhode Island
4
Wisconsin
4
Australia
3
more ...