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Nelsonite is composed principally of ilmenite and apatite. Ilmenite, FeTiO3, is a black, opaque, metallic and slightly magnetic mineral that is composed of 36.8 percent iron, 31.6 percent titanium, and 31.6 percent oxygen.Apatite, a light-colored, non-metallic mineral, is composed of calcium, phosphorous, oxygen, and fluorine or chlorine; its composition may be expressed by the formula Ca3(F,Cl)(PO4)3.
Nelsonite is named for Nelson County, Virginia where it was first found near Roseland. It occurs in Nelson and Amherst counties in dike-like bodies that are as much as 2000 feet long. It is also present in eastern Roanoke County. Deposits of nelsonite were a major source of ilmenite in Virginia. The titanium dioxide that was recovered from ilmenite was used in the manufacture of paint pigments. ). This specimen was collected in the late 90's from near Bryant, Virginia.
Nelsonite - (igneous rock)
"Amherst and Nelson Counties-Apatite makes up from 3 to 30 percent of the rock called nelsonite in a 13-mile long and 2 1/2 mile wide belt that extends from north of Bryant, Nelson County to Piney River on the Amherst-Nelson County Line and in the vicinity of Lovingston, near Davis Creek (Ross, 1934)."
from: Dietrich, R. V., 1990, Minerals of Virginia
"A second important and new occurrence of rutile is found in the Amherst-Nelson counties area, Virginia, as dike like bodies of an even-granular, ultrabasic igneous rock (nelsonite6) composed essentially of the ore minerals ilmenite and apatite with sometimes rutile as the dominant mineral."
from: Watson T. L., Mineral Resources of Virginia (1907)
"Named for Nelson County, this rock is composed of minerals that contain the element titanium. Nelsonite was an important commercial source of titanium several years ago. Titanium is a metal that is noted for its strength, lightness and toleration of high temperature. Nelsonite is an igneous rock that is found around the community of Bryant, near Roseland, Virginia."
"Nelsonites have a characteristically high concentration of Ti, which results in the formation of ilmenite, Ti-rich magnetite, or both. They are also apatite rich, often with 30–50 percent of this mineral. In addition, they are usually associated with anorthosites* (intrusive igneous rocks that are almost entirely plagioclase feldspar, usually labradorite). Nelsonites are magmatic in origin. It is believed that the
iron-titanium-phosphorous-oxide magmas from which they crystallize result from liquid immiscibility within a silicate magma, intense fractionation of some parent magma, or
partial melting of Fe- and P-rich rocks in the earth’s crust"
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Fossils Shells, etc.
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