Titanosapphire

Stoichometric checkerboard compounds between the isostructural gemstones of
leukosapphire and tistarite (these share the hematite structure)

Hematite can be a third end-member.
It is mechanically weaker but brings conductivity.
Possibly making for a tunable semiconcuctor.

• White sapphire Al₂O₃
• Tistarite Ti₂O₃
• Hematite Fe₂O₃

See: Simple crystal structures of especial interest

Related pages

• neo-polymorph & Pseudo phase diagram
• leukosapphire & tistarite

Other neo-polymorphs:

• dialondeite, stishotile, …