1) Trigonal mineral
Found on
https://www.crosswordclues.com/clue/leifite
Leifite is a rare tectosilicate. Tectosilicates are built on a framework of tetrahedra with silicon or aluminium at the centre and oxygen at the vertices; they include feldspars and zeolites, but leifite does not belong in either of these categories. It is a member of the leifite group, which includes telyushenkoite (Cs,Na,K)Na6(Be2Al3Si15O39) and...
Found on
http://en.wikipedia.org/wiki/Leifite
(Hydrated Sodium Beryllium Aluminum Silicate Hydroxide Fluoride) Leifite is a rather rare and obscure beryllium silicate mineral. It forms in rare rocks known as agpaites which are igneous rocks of unusual concentrations. They are characterized by high concentrations of alkali metals especially sodium and low concentrations of...
Found on
https://www.encyclo.co.uk/local/23719
No exact match found.
