Ilmenite
An iron–titanium oxide abundant in lunar mare basalts and common in eucrites and Martian meteorites.
Key facts
- Formula
- FeTiO3
- Family
- Oxides
- Crystal system
- Trigonal
What it is
Ilmenite is an oxide in which iron and titanium alternate in layers. It is weakly magnetic and dense. It is named after the Ilmen Mountains in Russia.
Where it is found
It is a major mineral in high-titanium lunar basalts from Apollo 11 and Apollo 17, sometimes making up a fifth of the rock. It occurs in smaller amounts in eucrites, shergottites, ordinary chondrites and many lunar meteorites. Lunar ilmenite has been studied as a possible source of oxygen for future Moon bases.
How it is recognised
It is black with a metallic lustre and a black to brownish streak. In polished section it is grey-brown with strong reflection colours under polarised light.
Did you know?
Heating ilmenite with hydrogen releases water, one way that future explorers might make oxygen on the Moon.
Ilmenite traps helium from the solar wind, including the rare isotope helium-3.