2.8" Golden-Brown, Radiating Astrophyllite - Kola Peninsula, Russia
This is a formation of golden-brown, radiating astrophyllite crystals in a quartzite matrix. It was collected from Eveslogchorr Mountain in the Kola Peninsula or Russia.
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, typically exhibiting golden-yellow to brown coloration. 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.