Nelsonite

This article is about the rock and ore. For the beetle genus, see Nelsonites.
Nelsonite
Igneous rock
A speckled rock with black (ilmenite) and white (apatite) grains
Nelsonite from Nelson County, Virginia
Composition
Ilmenite and apatite
Identification[1]
Formula FeO.TiO2.nFe2O3

Ca3(F,Cl)(PO4)3

Hardness 5 - 6
Specific gravity 3.7 - 4.1 bulk; ilmenite: 4.5-5.0
Streak ilmenite: black to brownish-red

apatite: white

Color black metallic and light-colored
Habit even-granular texture
Luster metallic to sub-metallic
Fracture conchoidal
Tenacity brittle
Texture holocrystalline

Nelsonite is an igneous rock primarily constituted of ilmenite and apatite, with anatase, chlorite, phosphosiderite, talc and/or wavellite appearing as minor components. Rocks are equigranular with a grain size around 2 – 3 mm.[2] The black ilmenite is slightly magnetic while the whitish apatite is not.[3]

  1. ^ Cite error: The named reference BUL_3A was invoked but never defined (see the help page).
  2. ^ Kolker, Allan (1982). "Mineralogy and Geochemistry of Fe-Ti Oxide and Apatite (Nelsonite) Deposits and Evaluation of the Liquid Immiscibility Hypothesis". Economic Geology. 77 (5): 1146–1158. CiteSeerX 10.1.1.918.2121. doi:10.2113/gsecongeo.77.5.1146.
  3. ^ Cite error: The named reference PVCC was invoked but never defined (see the help page).