Diamond Hill, Cumberland, Providence Co., Rhode Island, USA
|Latitude & Longitude (WGS84):||41° 59' North , 71° 24' West|
|Latitude & Longitude (decimal):||41.98333,-71.40000|
A prominent hill covering about one-third of a square mile, at least one-third of which is either quartz or highly silicified felsite. The quartz was formerly quarried, crushed and powdered for use as road metal, poultry grit, roofing gravels, fireproof brick and fire sand. It was also used as crushed stone for concrete (Warren and Powers, 1914).
Felsite is mostly light green to gray ignimbrites and ash flow tuffs of the Late Proterozoic Esmond Igneous Suite.
Epimorphs of quartz after barite (and fluorite) are frequently found.
Mineral ListMineral list contains entries from the region specified including sub-localities
14 valid minerals.
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.
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298.9 - 323.2 Ma
|Narragansett Bay Group - Rhode Island Formation|
Age: Pennsylvanian (298.9 - 323.2 Ma)
Stratigraphic Name: Rhode Island Formation
Description: In northern Rhode Island, consists of gray to black, fine- to coarse-grained quartz arenite, litharenite, shale, and conglomerate, with minor beds of anthracite and meta-anthracite. In southern Rhode Island, consists of meta-sandstone, meta-conglomerate, schist, carbonaceous schist, and graphite. Plant fossils are common.
Comments: Part of Esmond-Dedham Subterrane. Narragansett Bay Group - deposited upon older rocks of both West Bay and East Bay parts of the Esmond-Dedham subterrane.
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. 
Localities in this Region
- Rhode Island
- Providence Co.
- Diamond Hill
- Providence Co.
Robinson, Samuel (1825): A Catalogue of American Minerals, with Their Localities, p. 80.
Jackson, Charles T. (1840). Report on the geological and agricultural survey of the State of Rhode-Island (Providence: B. Cranston), p. 51-52.
Kunz G. F. (1892) Gems and Precious Stones of North America. (NY: The Scientific Publishing Company),p. 133.
Barber, Raymond J. and Mears, Henry S. (1906): An investigation of the quartz deposit at Diamond Hill, R.I. (Massachusetts Institute of Technology, Dept. of Mining Engineering and Metallurgy).
Emerson, B. K. and Perry, J. H. (1907). The green schists and associated granites and porphyries of Rhode Island. (USGS Bulletin 311), p. 56.
Warren, C. H. and Powers, Sidney (1914). Geology of the Diamond Hill - Cumberland District in Rhode Island - Massachusetts. (Bulletin of the Geological Society of America 25:435-476).
Fisher, Lloyd W. and Gedney,Edwin K. (1926): Notes on the mineral localities of Rhode Island; I. Providence County (American Mineralogist 11:334-340)
Miller, C.E.(1971): Rhode Island Minerals and Their Locations, O. D. Hermes, Ed. (University of Rhode Island, Kingston)