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:
Keyword(s):
 
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

Jamestown Mining District, Mother Lode belt, Tuolumne Co., California, USAi
Regional Level Types
Jamestown Mining DistrictMining District
Mother Lode beltBelt
Tuolumne Co.County
CaliforniaState
USACountry

This page is currently not sponsored. Click here to sponsor this page.
Key
Latitude & Longitude (WGS84):
37° North , 120° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~4km
Locality type:


Location: The Jamestown district is in western Tuolumne County. It consists of that portion of the Mother Lode belt that extends from French Flat southeast through Rawhide, Jamestown, Quartz Mountain, and the town of Stent to the vicinity of the Belcher mine, a distance of about eight miles. It also has been called the "Jimtown" district.

History: The streams and rich surface ores were first worked in the gold rush. Jamestown was established in 1848 by Colonel George F. James, a lawyer. Hydraulic mining began at Stent soon afterward, and the lode mines were active from the 1860s on. The placers at nearby Campo Seco yielded S5.5 million and those at Jamestown S3 million. From around 1890 to World War I lode mining was a major industry; in 1906 more than 300 stamps were "dropping" in the various mills. There was some a activity again during the 1920s and appreciable activity during the 1930s. There has been minor prospecting and development work in recent years at a few of the mines. The value of the total output of this district is estimated at more
than $30 million (period values).

Geology: In the north portion of the district, the deposits occur along a northwest-striking contact with serpentine to the southwest and phyllite, slate, and metaconglomerate to the northeast (fig. 16). In the central and south portion, the deposits are at or near the contact between massive greenstones and slates on the west and chlorite and amphibolitc schist to the east. Latite of Tuolumne Table Mountain crosses the belt north of Jamestown, and Tertiary gravel deposits underlie the latite in the vicinity of the town of Rawhide and to the southwest. At Quartz Mountain the Mother Lode belt swings from a northwest-southeast strike to almost due south.

Ore Deposits: Outcrops consist of massive quartz veins up to several tens of feet in thickness, adjacent bodies of ankerite-quartz-mariposite rock which sometimes are scores of feet thick, as well as bodies of mineralized schist and numerous parallel quartz stringers. These deposits often contain abundant disseminated sulfides (as much as eight to 10 percent of the total rock), which are mostly pyrite. The gold occurs in the native state or with pyrite. Milling-grade ore usually averaged 1/7 to 1/3 ounce gold per ton, but the ore shoots were large. The ore shoots had stoping lengths of as much as 400 feet or more, and several veins were mined to inclined depths of several thousand feet. A number of high-grade pockets have been found in this district. In places silver is abundant, and tellurides have been encountered.

Mines: Alabama ($150,000), Alameda, Anderson, App-Heslep ($6.5 million), Belcher, Crystalline ($100,000), Defender, Dutch-Sweeney ($3 million), Erin-go-bragh ($282,000), Golden Rule, Harvard ($2 million to $3 million), Hitchcock, Jumper ($5 million), Mazeppa, New Era, Nugget, Omega, Rappahannock, Rawhide ($6 million), Santa Ysabel ($1.5 million).

Regions containing this locality

Pacific OceanOcean
North America PlateTectonic Plate

Select Mineral List Type

Standard Detailed Strunz Dana Chemical Elements

Mineral List

Mineral list contains entries from the region specified including sub-localities

11 valid minerals.

Detailed Mineral List:

Ankerite
Formula: Ca(Fe2+,Mg)(CO3)2
Reference: U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
Azurite
Formula: Cu3(CO3)2(OH)2
Reference: Aubury, Lewis E. (1902), The copper resources of California: California Mining Bureau Bulletin 23: 201; Logan, Clarence August (1949), Mines and mineral resources of Tuolumne County, California: California Journal of Mines and Geology: 45: 53-54; Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 95; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 228.
Calcite
Formula: CaCO3
Reference: Sharwood, William J. (1911), Notes on tellurium-bearing gold ores: Economic Geology: 6: 286; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 125.
Chalcopyrite
Formula: CuFeS2
Reference: U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
Dolomite
Formula: CaMg(CO3)2
Reference: Sharwood, William J. (1911), Notes on tellurium-bearing gold ores: Economic Geology: 6: 286; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 125.
Gold
Formula: Au
Hessite
Formula: Ag2Te
Description: Evidenced by California Division of Mines and Geology specimen # 13617.
Reference: Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 219.
Malachite
Formula: Cu2(CO3)(OH)2
Reference: Aubury, Lewis E. (1902), The copper resources of California: California Mining Bureau Bulletin 23: 201; Logan, Clarence August (1949), Mines and mineral resources of Tuolumne County, California: California Journal of Mines and Geology: 45: 53-54; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 228.
Pyrite
Formula: FeS2
Reference: U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
Quartz
Formula: SiO2
Reference: U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
Tetradymite
Formula: Bi2Te2S
Reference: Sharwood, William J. (1911), Notes on tellurium-bearing gold ores: Economic Geology: 6: 286; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 125.

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
Chalcopyrite2.CB.10aCuFeS2
Hessite2.BA.60Ag2Te
Pyrite2.EB.05aFeS2
Tetradymite2.DC.05Bi2Te2S
Group 4 - Oxides and Hydroxides
Quartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
Ankerite5.AB.10Ca(Fe2+,Mg)(CO3)2
Azurite5.BA.05Cu3(CO3)2(OH)2
Calcite5.AB.05CaCO3
Dolomite5.AB.10CaMg(CO3)2
Malachite5.BA.10Cu2(CO3)(OH)2

List of minerals arranged by Dana 8th Edition classification

Group 1 - NATIVE ELEMENTS AND ALLOYS
Metals, other than the Platinum Group
Gold1.1.1.1Au
Group 2 - SULFIDES
AmBnXp, with (m+n):p = 2:1
Hessite2.4.2.1Ag2Te
AmBnXp, with (m+n):p = 1:1
Chalcopyrite2.9.1.1CuFeS2
AmBnXp, with (m+n):p = 2:3
Tetradymite2.11.7.1Bi2Te2S
AmBnXp, with (m+n):p = 1:2
Pyrite2.12.1.1FeS2
Group 14 - ANHYDROUS NORMAL CARBONATES
A(XO3)
Calcite14.1.1.1CaCO3
AB(XO3)2
Ankerite14.2.1.2Ca(Fe2+,Mg)(CO3)2
Dolomite14.2.1.1CaMg(CO3)2
Group 16a - ANHYDROUS CARBONATES CONTAINING HYDROXYL OR HALOGEN
Azurite16a.2.1.1Cu3(CO3)2(OH)2
Malachite16a.3.1.1Cu2(CO3)(OH)2
Group 75 - TECTOSILICATES Si Tetrahedral Frameworks
Si Tetrahedral Frameworks - SiO2 with [4] coordinated Si
Quartz75.1.3.1SiO2

List of minerals for each chemical element

HHydrogen
H AzuriteCu3(CO3)2(OH)2
H MalachiteCu2(CO3)(OH)2
CCarbon
C AnkeriteCa(Fe2+,Mg)(CO3)2
C AzuriteCu3(CO3)2(OH)2
C MalachiteCu2(CO3)(OH)2
C CalciteCaCO3
C DolomiteCaMg(CO3)2
OOxygen
O AnkeriteCa(Fe2+,Mg)(CO3)2
O QuartzSiO2
O AzuriteCu3(CO3)2(OH)2
O MalachiteCu2(CO3)(OH)2
O CalciteCaCO3
O DolomiteCaMg(CO3)2
MgMagnesium
Mg AnkeriteCa(Fe2+,Mg)(CO3)2
Mg DolomiteCaMg(CO3)2
SiSilicon
Si QuartzSiO2
SSulfur
S PyriteFeS2
S ChalcopyriteCuFeS2
S TetradymiteBi2Te2S
CaCalcium
Ca AnkeriteCa(Fe2+,Mg)(CO3)2
Ca CalciteCaCO3
Ca DolomiteCaMg(CO3)2
FeIron
Fe PyriteFeS2
Fe AnkeriteCa(Fe2+,Mg)(CO3)2
Fe ChalcopyriteCuFeS2
CuCopper
Cu ChalcopyriteCuFeS2
Cu AzuriteCu3(CO3)2(OH)2
Cu MalachiteCu2(CO3)(OH)2
AgSilver
Ag HessiteAg2Te
TeTellurium
Te HessiteAg2Te
Te TetradymiteBi2Te2S
AuGold
Au GoldAu
BiBismuth
Bi TetradymiteBi2Te2S

References

Sort by

Year (asc) Year (desc) Author (A-Z) Author (Z-A)
Irelan, William, Jr. (1888b), Eighth annual report of the State Mineralogist [includes mineral resources of the State, with contributions by W.A. Goodyear, H.A. Whiting, and Stephen Bowers]: California Mining Bureau. (Report 8), 946 pp.: 660-664.
Fairbanks, Harold W. (1890), Geology of the Mother Lode region: California Mining Bureau. (Report 10): 10: 50-56.
Turner, Henry Ward & F.L. Ransome (1897), Description of the gold belt; description of the Sonora sheet: USGS Geologic Atlas, Sonora folio (Folio No. 41), 7 pp.
Ransome, Frederick Leslie (1900), Description of the Mother Lode district, California: USGS Geological Atlas, Mother Lode (folio No. 63), 11 pp.
Storms, William H. (1900), The Mother Lode region of California: California Mining Bureau. Bulletin 18: 128-141.
Tucker, W. Burling (1916), Amador, Calaveras, Tuolumne Counties: California Journal of Mines and Geology, California Mining Bureau. (Report 14): 14: 1-172; […(abstract): Geol. Zentralbl., Band 27: 396 (1922)]: 145-146, 149-151, 152-153, 159-160.
Logan, Clarence August (1928), Tuolumne County, Butte County: California Mining Bureau. (Report 24): 24: 8-9.
Knopf, Adolf (1929), The Mother Lode system of California: USGS Professional Paper 157, 88 pp.; […(abstract): Engineering & Mining Journal: 128: 24 (1929); […Geol. Zentralbl., Band 41: 364-367 (1930)].
Logan, Clarence August (1934), Mother Lode Gold Belt of California: California Division Mines Bulletin 108, 221 pp.: 171-172.
Eric, J.H., A.A. Stromquist & C.M. Swinney (1955), Geology and mineral deposits of the Angels Camp and Sonora quadrangles, Calaveras and Tuolumne Counties, California: California Division Mines Special Report 41, 55pp.
Clark, Wm. B. (1970a) Gold districts of California: California Division Mines & Geology Bulletin 193.
Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 35 (map 2-21).

Localities in this Region


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.
 
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 19:14:01 Page generated: June 26, 2019 23:44:19
Go to top of page