Gibbsite (RARE from Brazil!) Matioli Coll.

Item Description

Gibbsite, an Al-hydroxide bog iron mineral, is EXTREMELY RARE from any locality in Minas Gerais. This is a UNIQUE specimen from a most obscure locality, that is not listed by MINDAT. The sculptural, large mounded nodular mass is composed of banded, translucent, vitreous luster, gray to colorless gibbsite with a partial oxide coating. The large nodules at the top really dramatize this 360-degree rarity from the Matioli Collection. This piece is from near the renowned Imperial Topaz deposits in Ouro Preto. Only one we have seen....from an old species collection bought in Brazil.