View source for Cerium

[[File:E and Klm.gif|350px|thumb|right|'''Young’s modulus and the lattice-scaled stiffness
for selected materials''' – See page [[lattice scaled stiffness]] for details.]]

Cerium is not the most abundant element. But also not extremely rare.<br>

Cerium is possibly of interest for early primitive [[force applying mechanosynthesis]] <br>
as CeO<sub>2</sub> has a particularly high [[lattice scaled stiffness]]. <br>

The [[lattice scaled stiffness]] of [[pyrite]] FeS<sub>2</sub> ([[pyrite structure]]) is still a bit higher.

CeO<sub>2</sub> is cubic, space group: Fm3m, #225
Natural occuring as the '''cerianite''' <br>
solid solution mixing with Thorium substituting for cerium. <br>
Since ThO<sub>2</sub> has the same structure it seems likely that <br>
the whole range of [[checkerboard compound]]s should be stable and accessible.

Natural thorium is rather weakly radioactive (like natural uranium) <br>
thus safely as a solid non dusting mineral with a bit of care.

== Related ==

* [[Chemical element]]
* [[Lattice scaled stiffness]]

== External links ==

* https://en.wikipedia.org/wiki/Cerium(IV)_oxide
* https://en.wikipedia.org/wiki/Cerianite-(Ce) 7.3g/ccm
* https://en.wikipedia.org/wiki/Thorium_dioxide
* https://en.wikipedia.org/wiki/Thorianite Mohs 6.5 to 7.0 9.7g/ccm