Ellingsenite
Ellingsenite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₅Ca₆Si₁₈O₃₈(OH)₁₃·6H₂O.
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 4; specific gravity 2.32; White streak; Vitreous individuals, silky aggregates luster; optically biaxial.
IMA symbol Elg, IMA status: approved, named in 2009.
A low-temperature mineral in vesicles in hydrothermally altered phonolite.
It is found associated with Aegirine, albite, manganoneptunite, microcline, natrolite, polylithionite.
The mineral was named to honor Dr. Hans Vidar Ellingsen (b. 1930), who has been chairman of the Norwegian Amateur Geological Society and who collected the first specimens.
Index entry. This entry combines official IMA/RRUFF species data with published physical-property data — a full written entry hasn’t been published yet.
Browse more E minerals or help write this entry.