Chromite Value, Price, and Jewelry Information

Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC-BY-SA-3.0], via Wikimedia Commons

Chromite

Chromite is shiny and black, and makes a curious-looking cabochon with no special attraction. Occasionally, a cabochon has a reddish color. The stones have little value because the material is extremely abundant but are cut as curiosities only.

Chromite Information

Data Value
Name Chromite
Is a Variety of Spinel
Colors Black, reddish brown.
Crystallography Isometric. Octahedral crystals up to 1 cm on edge; massive.
Refractive Index 2.08-2.16
Luster Submetallic.
Hardness 5.5
Fracture Uneven
Specific Gravity 4.5-4.8
Cleavage None
Luminescence None
Luminescence Present No
Transparency Opaque, translucent in thin splinters.
Absorption Spectrum Not diagnostic.
Formula

FeCr2 O4

Pleochroism

None.

Optics

RI = 2.08-2.16. Isotropic.

Chromite group, extensive solid-solution series.

Note: Magnesiochromite = MgCr2 O4; Hercynite = FeAl2O4.

Optics: R.I. = 2.08-2.16. Isotropic.

Occurrence: in igneous rocks rich in olivine; in serpentines; in stream and beach sands. Sometimes in massive deposits of large size.

California; Oregon; Washington; Wyoming; Maryland; North Carolina; Pennsylvania.

Canada; Cuba; Norway; USSR; France; Zimbabwe; India.

Stone Sizes: Any size could be cut from massive material. The possibility exists for some deep reddish crystals to contain very tiny facetable areas, but thus far none have been discovered.

Comments: Chromite is shiny and black, and makes a curious-looking cabochon with no special attraction. Occasionally, a cabochon has a reddish color. The stones have little value because the material is extremely abundant but are cut as curiosities only.

Sometimes weakly magnetic.

Name: In allusion to the composition.