Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsBooks & Magazines
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryMineral Photography

Mary Harrison Mine, Mary Harrison group, Coulterville, Coulterville District, Mother Lode Belt, Mariposa Co., California, USA

This page is currently not sponsored. Click here to sponsor this page.
Latitude & Longitude (WGS84): 37° 42' 31'' North , 120° 11' 53'' West
Latitude & Longitude (decimal): 37.70861,-120.19806

A former Au mine located in sec. 3, in the NE¼NE¼ sec. 10, and in sec. 11, T3S, R16E, MDM, 0.2 km (800 feet) SSW of Coulterville (1 mile S of Coulterville on highway 49). Discovered in 1852. Operated during the periods 1852-1887, 1878-1894, and 1897-1904. MRDS database stated accuracy for this location is 1,000 meters.

Mineralization is a vein deposit in a thrust fault fissure, hosted in Late Jurassic slate, serpentinite, greenstone and schist. The ore body strikes N50W and dips 60-75NE at a thickness of 6.1 meters and a width of 30.48 meters. Controls for ore emplacement included the footwall side of a quartz sheet. Black slate is one of the host rocks. The greenstone was derived from pyroxene andesite of Paleozoic Calaveras Formation from the hanging wall. The footwall slate is probably part of the Upper Jurassic Mariposa Formation. The Mary Harrison vein is traceable from the county line on the N to the Virginia Mine of the S. It is characterized by a prominent sheet of massive milky quartz 4 to 290 feet thick between irregular, ribboned masses of quartz-mariposite-pyrite rock, the upper parts of which are commonly converted to porous, earthy masses of yellowish brown iron and silica oxides. Alteration is local and is oxidation by H2SO4. Local rocks include Jurassic marine rocks, unit 1 (Western Sierra Nevada and Western Klamath Mountains).

Workings include underground openings with a total length of 2,133.6 meters and an overall depth of 365.76 meters. They are comprised of a 1,200 foot vertical shaft with levels at 100 foot intervals. A second inclined shaft has levels at 100 foot intervals. There is also a ventilation shaft and more than 5,000 feet of drifts.

Production data are found in: Bowen & Gray (1957).

Production information: Between $330,000 and $400,000 (period values) of Au were produced between 1895 & 1903 at $5 Au/ton in 1897.

Mineral List

5 valid minerals.

Rock Types Recorded

Note: this is a very new system on mindat.org and data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

Regional Geology

This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.

Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org

Mesozoic - Paleozoic
66 - 541 Ma
Undivided pre-Cenozoic metavolcanic rocks, unit 2 (undivided)

Age: Phanerozoic (66 - 541 Ma)

Stratigraphic Name: Hodge Volcanic Series; Franklin Canyon Formation (part); Slate Creek Complex (part)

Description: Undivided pre-Cenozoic metavolcanic rocks. Includes latite, dacite, tuff, and greenstone; commonly schistose.

Comments: Klamath Mountains, Sierra Nevada, Mojave Desert, and other areas. Miscellaneous volcanic and metavolcanic rocks, probably mostly Jurassic in age

Lithology: Major:{mafic volcanic,greenstone}, Minor:{felsic volcanic}, Incidental:{amphibolite, gabbro}

Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. [133]

Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.


Aubury, Lewis E. (1904), Register of Mines and Minerals, Mariposa County, California, California State Mining Bureau: 12.

Castello, W.O. (1921), Mines and Mineral Resources of Mariposa County: California Mining Bureau; 17th Report of the State Geologist: 124-125.

Laizure, Clyde McK (1928), Mariposa, Madera Counties: California Mining Bureau. Report 24: 100.

Knopf, Adolf (1929), The Mother Lode system of California: USGS PP 157, 88 pp.; […(abstract): Engineering & Mining Journal: 128: 24 (1929); …Geol. Zentralbl., Band 41: (1930)]: 35, 36, 40.

Logan, Clarence August (1934), Mother Lode gold belt of California: California Division Mines Bulletin 108, 221 pp.: 185.

Bowen, O.E., Jr. & C.H. Gray, Jr. (1957), Mines and mineral deposits of Mariposa County, California: California Journal of Mines and Geology: 53(1-2): 130-132, 202.

Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 335.

Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 169, 220-221.

USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10030851, 10110792, 10261062.

U.S. Bureau of Mines, Minerals Availability System (MAS) file ID #0060430063.

Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2020, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: January 27, 2020 18:42:08 Page generated: October 16, 2017 16:47:10
Go to top of page