Brookite

• Titanium is common in earths crust (and in space)
• Hardness is decent
• Crystal structure is simple
• Unit cell is not a bit fragmented (choose other unit cell?)

Overall a good structural base material for gemstone metamaterial technology for larger scale construction.

• Formula: TiO₂
• Hardness Mohs 5.5 to 6.0
• Crystal system: orthorhombic
• Density ~4,133g/ccm
• Refractive index: n_α = 2,583, n_β = 2,584, n_γ = 2,700 – quite high

Related

• Titanium

Other polymorphs of same formula:

• Anatase
• Rutile
• Tistarite

External links

• Wikipedia: Brookite
• mineralientalas.de: Brookite (3D structure)