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

Stilbite Subgroup from
Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA


00359050017605092428271.jpg
Stilbite Subgroup, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
03999270017272025507636.jpg
Stilbite Subgroup

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
07271620017272019629220.jpg
Stilbite-Ca, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
08295130017598562183409.jpg
Stilbite Subgroup, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
09939630017597850573323.jpg
Stilbite Subgroup, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
03999270017272025507636.jpg
Stilbite Subgroup

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
00250600017367349864843.jpg
Stilbite-Ca, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
03618260017597852055684.jpg
Stilbite Subgroup, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
02253670017597973654515.jpg
Stilbite Subgroup, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
05869190017272025535890.jpg
Stilbite Subgroup

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
05447400017272019679953.jpg
Stilbite-Ca, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
08295130017598562183409.jpg
Stilbite Subgroup, etc.

Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
Locality type:Road Cutting
Classification
Species:'Stilbite Subgroup' (not an IMA approved species)
Formula:M6-7[Al8-9Si27-28O72] · nH2O
Formation:Primary
Comments:Crystal aggregates to about 2.5 cm associated with barite, calcite, pyrite, quartz, sphalerite, and fluorite. Some of the best Connecticut stilbite was found here sometimes richly mineralized in voids in hydrothermal veins and fractures, covering other hydrothermal minerals or on schist, pegmatite or granite.

Habit:divergent fan-like to bow-tie aggregates of bladed, tabular crystals with pointed terminations
Colour:white to creamy yellow
Quality for species:Good crystals or rich for species - important (!)
Abundance at site:Common
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified
Associated Minerals Based on Photo Data:
Quartz26
Calcite15
Heulandite-Ca7
Fluorite6
Pyrite6
Galena5
Sphalerite3
Baryte1
Heulandite Subgroup1
Data
Mineral Data:Click here to view Stilbite Subgroup data
Locality Data:Click here to view Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
Photo GalleryView Gallery (31 photos)
Data Identifiers
Mindat Occurrence Record ID:96386
Long-form Identifier:1:3:96386:0
GUID (UUID V4):0
Nearest other occurrences of Stilbite Subgroup
0.9km (0.5 miles) ⓘWhispering Pines residential construction site, Thomaston, Litchfield County, Connecticut, USA
1.6km (1.0 miles) ⓘState Routes 8 and 222 interchange, Thomaston, Litchfield County, Connecticut, USA
2.6km (1.6 miles) ⓘNorthfield Brook Dam, Thomaston, Litchfield County, Connecticut, USA
5.0km (3.1 miles) ⓘReynolds Bridge, Thomaston, Litchfield County, Connecticut, USA
5.9km (3.7 miles) ⓘWaterbury Road quarry, Thomaston, Litchfield County, Connecticut, USA
10.3km (6.4 miles) ⓘSouth Main Street construction site, Torrington, Litchfield County, Connecticut, USA
11.2km (7.0 miles) ⓘBlue Stone Quarry, Waterbury, New Haven County, Connecticut, USA
12.8km (8.0 miles) ⓘRoute 73 quarry, Waterbury, New Haven County, Connecticut, USA
18.1km (11.2 miles) ⓘWoodhaven, Waterbury, New Haven County, Connecticut, USA
18.2km (11.3 miles) ⓘNonnewaug River Industrial Park, Woodbury, Litchfield County, Connecticut, USA
References
Rocks & Minerals: 34: 3.
Zodac, Peter (1959) Minerals at Thomaston Dam, Conn. Rocks & Minerals, 34 (1) 3-48 doi:10.1080/00357529.1959.11766706
Segeler, Curt G., Molon, Joseph (1985) The Thomaston Dam Site Thomaston, Connecticut. Rocks & Minerals, 60 (3) 119-124 doi:10.1080/00357529.1985.11764386
Vogt, Wolfgang. (1991), Rediscovering Thomaston Dam. Lapidary Journal: April.
 
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 16:42:22
Go to top of page