Virginia nelsonites

Region East, Southeast
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Area of documented deposits; nelsonite dike-like rocks associated with the Roseland-Piney River mineral district of Nelson and Amherst Counties, Virginia. The focus area includes the Roseland anorthosite, border gneiss, and charnockite, as shown in the state geologic map.
Identified resources Historical production of titanium (ilmenite, rutile).
Production Ilmenite was mined 1901-1958 from nelsonite dikes, anorthosite, and associated saprolites.
Status Past mining (ended 1971).
Estimated resources Unknown.
Geologic maps Herz and Force (1987), scale 1:24,000; Carter (2008a, b), scale 1:24,000.
Geophysical data Inadequate Rank 4 aeromagnetic and Rank 5 aeroradiometric coverage.
Favorable rocks and structures Nelsonite, an unusual rock consisting mainly of apatite and ilmenite with or without rutile, and ferrodiorite associated with Mesoproterozoic anorthosite near Roseland in the Blue Ridge province and with the Mesoproterozoic Montpelier Anorthosite in the eastern Piedmont.
Deposits Piney River (Roseland District) (MRDS dep_id: 10179636), Montpelier mine (MRDS dep_id: 10068333).
Evidence from mineral occurrences MRDS; Aleinikoff and others (1996).
Geochemical evidence Average grade in saprolite resource estimated at 7% TiO2; rutile in anorthosite averages 4-5% TiO2. Favorable mineralogy and rock type.
Geophysical evidence Unknown.
Evidence from other sources See Fish (1962); Fish and Swanson (1964); Hickman (1947).
Comments Scattered small deposits typically rutile>ilmenite; nelsonite dikes up to 2,000 ft long by 65 ft wide; mining to depths of 100 ft. USBM conducted core drilling in Roseland area as well as the Bush-Hutchins ilmenite mine area in Roanoke County, Virginia. Roseland district is a past-produced of titanium (rutile) from contact metamorphosed Mesoproterozoic country rocks, charnockite and border gneiss, that were intruded by the Roseland Anorthosite.
Cover thickness and description Exposed bedrock to thin cover; bedrock to <10 m.
Authors Nora K. Foley, William L. Lassetter, J. Wright Horton, Jr.
New data needs Geophysical data and geochemical analyses; the REE, V content of remaining resources are unknown.
Geologic mapping and modeling needs Geologic mapping sufficient, locally may be improved.
Geophysical survey and modeling needs High resolution aeromagnetic and aeroradiometric coverage. Aeromagnetic data expected to image mafic rocks and associated structures, radiometric data can help with geologic mapping in vegetated terrane.
Digital elevation data needs Lidar complete.