Rubinite
A titanium garnet that condensed or crystallised among the first solids of the Solar System.
Key facts
- Formula
- Ca3Ti3+2Si3O12
- Family
- Silicates
- Crystal system
- Cubic
- First described
- the Allende and Vigarano CV3 chondrites, 2016
Rubinite was approved as a new mineral in 2016 from calcium-aluminium-rich inclusions in the Allende and Vigarano meteorites. It is named after Alan Rubin, an American meteorite scientist known for his work on chondrites. It is known only from meteorites.
What it is
Rubinite is a garnet, the mineral family of the red gemstones, in which reduced titanium, Ti3+, takes the place of aluminium. Garnets with reduced titanium can form only where oxygen is scarce, so rubinite is a sign of the oxygen-poor gas around the newborn Sun.
Where it is found
It occurs as grains a few micrometres across in melilite-rich calcium-aluminium-rich inclusions in Allende and Vigarano, two CV3 carbonaceous chondrites.
How it is recognised
It is identified with a scanning electron microscope, by its composition and by electron backscatter diffraction.
Did you know?
Rubinite is a refractory garnet: one of the few garnets that formed in the solar nebula rather than inside a planet.
Its name honours a person, not the colour red or the gem ruby.