rare hydrous potassium iron titanium silicate mineral named astrophyllite

astrophyllite rare potassium iron titanium silicate mineral inosilicate phyllosilicate collect fragile radiating stellate aggregate crystal star submetallic gleam contrast sharp opaque beautiful nature piece slice natural organic layered structure valuable attractive semiprecious stone precious glossy veins gemology mineralogy hardstone lithotherapy energy shape symbol shiny texture abstract surface textured geology selective focus hydrous named