Pinite
Fine-grained pseudomorphs after aluminosilicate minerals, especially cordierite , nepheline , topaz , andalusite , spodumene , feldspars and scapolite . Mineralogically, "pinite" is primarily composed of sericite mica (usually muscovite ) and may include some clay group minerals.
First reported from Pini adit, Aue, Erzgebirge, Saxony, Germany.