Tags: Chemical Substance, Mineral.
Siderophyllite is a rare member of the mica group of silicate minerals with formula KFe2+2Al(Al2Si2)O10(FOH)2.The mineral occurs in nepheline syenite pegmatites and granite and aplite greisens. It is associated with microcline and astrophyllite at Pikes Peak Colorado. It is also found in the alkali pegmatites of Mont Saint-Hilaire Quebec.It was first described in 1880 for an occurrence near Pikes Peak Colorado.
