Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
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 ElementsThe Rock H. Currier Digital LibraryGeologic TimeExplore Fossils
Minerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced 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 MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Hilton Gulch, Oak Ridge, Santa Clara County, California, USAi
Regional Level Types
Hilton GulchGulch
Oak RidgeRidge
Santa Clara CountyCounty
CaliforniaState
USACountry

This page is currently not sponsored. Click here to sponsor this page.
PhotosMapsSearch
Latitude & Longitude (WGS84):
37° North , 121° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~1km
GRN:
N25W70
Type:
Gulch
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Mindat Locality ID:
217334
Long-form identifier:
mindat:1:2:217334:7
GUID (UUID V4):
0


An occurrence in Hilton Gulch at Oak Ridge, N of Mount Hamilton & the Lick Observatory.

NOTE: Hilton Gulch is not listed in the USGS GNIS database.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


3 valid minerals.

Detailed Mineral List:

ⓘ Almandine
Formula: Fe2+3Al2(SiO4)3
Colour: Red
Description: Crystals to ½ inch (1.25 cm) occur in eclogites.
ⓘ Glaucophane
Formula: ◻[Na2][Mg3Al2]Si8O22(OH)2
ⓘ Margarite
Formula: CaAl2(Al2Si2O10)(OH)2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘAlmandine9.AD.25Fe2+3Al2(SiO4)3
ⓘGlaucophane9.DE.25◻[Na2][Mg3Al2]Si8O22(OH)2
ⓘMargarite9.EC.30CaAl2(Al2Si2O10)(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ Glaucophane◻[Na2][Mg3Al2]Si8O22(OH)2
Hⓘ MargariteCaAl2(Al2Si2O10)(OH)2
OOxygen
Oⓘ AlmandineFe32+Al2(SiO4)3
Oⓘ Glaucophane◻[Na2][Mg3Al2]Si8O22(OH)2
Oⓘ MargariteCaAl2(Al2Si2O10)(OH)2
NaSodium
Naⓘ Glaucophane◻[Na2][Mg3Al2]Si8O22(OH)2
MgMagnesium
Mgⓘ Glaucophane◻[Na2][Mg3Al2]Si8O22(OH)2
AlAluminium
Alⓘ AlmandineFe32+Al2(SiO4)3
Alⓘ Glaucophane◻[Na2][Mg3Al2]Si8O22(OH)2
Alⓘ MargariteCaAl2(Al2Si2O10)(OH)2
SiSilicon
Siⓘ AlmandineFe32+Al2(SiO4)3
Siⓘ Glaucophane◻[Na2][Mg3Al2]Si8O22(OH)2
Siⓘ MargariteCaAl2(Al2Si2O10)(OH)2
CaCalcium
Caⓘ MargariteCaAl2(Al2Si2O10)(OH)2
FeIron
Feⓘ AlmandineFe32+Al2(SiO4)3

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate
USA

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.

References

Holway, Ruliff S. (1904), Eclogites in California Journal of Geology: 12: 344-358; [(abstract): Geol. Zetralbl., Band 9: 515 (1907)]: 353.
Smith, James Perrin (1906), The paragenesis of the minerals in the glaucophane-bearing rocks of California: American Philosophical Society Proceedings: 45: 203
Pabst, Adolf (1931) The garnets in the glaucophane schists of California. American Mineralogist, 16 (8) 327-333
Pabst, A. (1955) Manganese content of garnets from the Franciscan schists. American Mineralogist, 40 (9-10) 919-922
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 196, 256.
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
Quick NavTopMineral ListOther RegionsReferences
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 3, 2026 09:12:17 Page updated: August 11, 2025 16:13:33
Go to top of page