Olivine

A type of stony-iron meterorite called "pallasite". The green parts are olivine. This is believed to be a material that can be found in large quantities at the core mantle boundary of larger rocky planets.

Basic properties:

• Mohs 6.5 to 7.0
• Orthorhombic – (Nesosilicate like topaz)
• (Nontrivial base cell?)

Two end members:

• iron-olivine: Fe₂SiO₄
• magnesium-olivine: Mg₂SiO₄

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• Fayalite Fe₂SiO₄ (Mohs 6.5-7)
  High pressure crystal structure γ-Fe₂SiO₄ is called Ahrensite – [1] – (nice cubic unit cell – Mohs 6 – 4.26g/ccm)
• Forsterite Mg₂SiO₄ (Mohs 7)
  Mid pressure crystal structure is called: Wadsleyite – (orthrombic – Mohs ? – 3.84g/ccm)
  High pressure crystal structure is called: Ringwoodite – (nice cubic unit cell – Mohs ? – 3.9g/ccm)

Suitability of these compounds as base materials for gemstone metamaterial technology seems quite good.

Some Trivia

Olivine is an extremely common mineral.
It is believed that there are large quantities of this stuff down at the core mantle boundary of Earth and above.
We know that from stony–iron meteorites called "pallasites" (very pretty to look at).
The asteroid psyche is believed to be the biggest arteroid in the asteroid belt that is mainly made out of pallasite.

Artificially mechanosynthesized ultra pure and flawless olivine would likely be colorless not green.

Gem grade olivine is called peridot.

External links

• Wikipedia: Olivine
• Wikipedia: Pallasite
• on www.mineralienatlas.de

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• https://en.wikipedia.org/wiki/16_Psyche
• https://en.wikipedia.org/wiki/Psyche_(spacecraft)
• https://www.nasa.gov/psyche

Related

• Colonization of the solar system
• Iron