.9" Dark Brown Niobophyllite on Feldspar - Malawi

Astrophyllite is a rare hydrous potassium iron titanium silicate mineral with the chemical formula (K,Na)3(Fe++,Mn)7Ti2Si8O24(O,OH)7. It commonly forms as radiating, bladed aggregates of soft and brittle crystals, colored golden-yellow to brown. Due to the fragile nature of astrophyllite crystals, they're usually left in situ (within surrounding matrix) for presentation. However, this hasn't stopped jewelers from incorporating polished astrophyllite specimens into jewelry.