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 Time
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 MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral Quiz
Photo SearchPhoto GalleriesSearch by ColorNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Littlejohn Occurrence, Alaska Peninsula District, Aleutians East Borough, Alaska, USA

This page is currently not sponsored. Click here to sponsor this page.
DisplayPhotosMapsSearch
 
 
Good example of how color anomaly evaluation focused on copper porphyry mineralization (Christie, 1974) might miss epithermal gold vein type mineralization.
Location: Two miles east of Littlejohn Lagoon, north side of north fork of creek. Probably anomaly no. 63 of Christie (1974).
Geology: Strongly argillized vesicular andesite containing areas of silicified rock. Initially reported as having rare quartz veins and disseminated Au and Hg (Trujillo and others, 1982), later work (Butherus, 1984) showed Au and Hg to be limited to vertical fault or shear that localizes reticulated quartz veins.
Workings: Christie (1974) reported brief reconnaissance geologic mapping and collection of a few silt samples as part of a porphyry copper evaluation. Trujillo and others (1982) and Butherus (1984) collected 269 samples and did geologic mapping, collecting 45 samples in 1982 and 224 in 1984. Their samples showed gold to 5.6 ppm and silver to 33.2 ppm whereas Christie's (1974) were at background levels.
Age: Pliocene or younger
Alteration: Propylitic alteration, inferred from presence of chlorite (Christie, 1974).

Commodities (Major) - Au, Hg; (Minor) - Ag, As
Development Status: No
Deposit Model: Epithermal gold vein, hot springs gold-silver, Hot spring disseminated gold (Si

Mineral List



3 entries listed. 2 valid minerals.

The above list 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

Butherus, D.L., 1984, Exploration and evaluation of northern Akun Island and Walrus Peak-Littlejohn areas, Aleut Native Corporation Lands, 1984: Resource Associates of Alaska, 14 p., 4 appendices (Report held by the Aleut Corporation, Anchorage, Alaska.) Christie, J.S., 1974, Aleut-Quintana-Duval 1974 joint venture, final report: Unpublished Quintana Minerals Corporation report, 24 p., 3 appendices, 2 maps. (Report held by the Aleut Corporation, Anchorage, Alaska.) Trujillo, R.S., Tapper, C.J., Alvarez, T.J., Porterfield, Ben, and Toupe, W.M., 1982, Exploration and evaluation of precious metal potential of portions of Aleut Corporation lands, southwest Alaska 1982: Resource Associates of Alaska unpublished report, 91 p, 33 maps, various scales. (Report held by the Aleut Corporation, Anchorage, Alaska.)

 
Mineral and/or Locality  
Mindat Discussions Facebook Logo Instagram Logo Discord Logo
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, 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.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 24, 2024 02:18:09 Page updated: January 25, 2015 15:55:58
Go to top of page