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Ilmenite Rings
Named for its place of discovery at Ilmen Lake in the Ilmen Mountains, Miask in the southern portion of
the Ural Mountains of Russia. Ilmenite forms as a primary mineral in mafic igneous rocks and is concentrated into layers by
a process called"magmatic segregation". It crystallizes out of a magma relatively early before most of the other minerals.
As a result, the heavier crystals of ilmenite fall to the bottom of the magma chamber and collect in layers. It is these layers
that constitute a rich ore body for titanium miners. Ilmenite also occurs in pegmatites and some metamorphic rocks as well
as in the sedimentary rocks that are formed from the weathering and erosion of them.
Ilmenite is a metallic to submetallic mineral that is generally iron black. At times it can form brightly
lustered intricately faceted crystals or radial clusters arranged in a rosette fashion. Platy hexagonal crystals with rhombohedral
faces on the edges can appear very similar to hematite's tabular habits. However hematite has a distinctly different streak.
Magnetite is also similar and easily confused with ilmenite, but ilmenite has a different crystal form and is not as strongly
magnetic. It is often associated with magnetite and therefore ilmenite is a minor ore of iron as the magnetite and ilmenite
are processed for their iron contents. Ilmenite is very rarely found in jewelry or as an ornamental
stone, although in Czarist Russia it was often polished and used as umbrella and walking cane handles. It takes a fine
polish and resembles hematite when worked into gemstones, but it is more lustrous and has a darker color than most hematite.
The ilmenite here was collected by me in the Lake Ellen kimberlite pipe near Channing, Mi.
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Very pretty 6x8 egg-shaped cab mounted on a size 9 hammered sterling silver band.
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Glossy 7x8 nearly oval, nearly round cabochon that I cut into this shape to save as much of the original stone as possible.
Set on a size 7½ hammered sterling silver band.
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