The Grassely Group is a chromium mine located in Tuolumne county, California at an elevation of 1,070 feet.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Elevation: 1,070 Feet (326 Meters)
Commodity: Chromium
Lat, Long: 37.90444, -120.50417
Map: View on Google Maps
Satelite View
MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.
Grassely Group MRDS details
Site Name
Primary: Grassely Group
Secondary: Claims: Last Chance
Secondary: Morning Glory
Secondary: May Faction
Secondary: Lopez Lease 1918
Commodity
Primary: Chromium
Location
State: California
County: Tuolumne
District: Peoria Flat Area
Land Status
Land ownership: Private
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.
Holdings
Not available
Workings
Not available
Ownership
Owner Name: Grassley, Eugene
Owner Name: George Everhart
Production
Not available
Deposit
Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Year First Production: 1914
Year Last Production: 1917
Years of Production:
Organization:
Significant: N
Deposit Size: S
Physiography
General Physiographic Area: Pacific Mountain System
Physiographic Province: Cascade-Sierra Mountains
Physiographic Section: Sierra Nevada
Mineral Deposit Model
Not available
Orebody
Not available
Structure
Type: R
Description: Extensive Shearing In Host Rock
Type: L
Description: Serpentinization Of Dunite
Alterations
Not available
Rocks
Name: Dunite
Role: Host
Age Type: Host Rock
Age Young: Late Jurassic
Analytical Data
Not available
Materials
Ore: Chromite
Comments
Comment (Workings): WORKINGS ON THE 3 CLAIMS CONSISTED OF SMALL TRENCHES, PITS, OPENCUTS AND SHALLOW CAVED SHAFTS.
Comment (Geology): DEPOSIT OCCURS IN NORTHERN PART OF THE WESTERN MOST OF TWO SERPENTINE BELTS THAT TREND NW-SE ACROSS THE COUNTY. THE BELT IS EXPOSED OVER AN AREA 30 KM BY 6 KM.
Comment (Deposit): DEPOSIT CONSISTS OF VERTICALLY DIPPING BANDS OF CHROMITE THAT STRIKE NW, EXCEPT AT THE MAY FACTION CLAIM WHERE THE ORE BANDS STRIKE N12W AND THE LIREATION OF THE ORE PITCHES 10 SE.
References
Reference (Deposit): CATER, F.W. JR., 1948, CDMG BULL 134, PART 3, CHAPT. 1, P. 26, 27
Reference (Production): CDMG BULL 134, PT. 3, CHAPT. 1, P. 26, 27.
California Gold
"Where to Find Gold in California" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in California. Read more: Where to Find Gold in California.
