Auction Win: Quartz (full of rainbows!)

Locality: Minas Gerais, Brazil

Size: Small Cabinet - 5.5 × 3.3 × 3.2 cm

Full of rainbows! This is a great piece from a new lot we just received. You’ll also see Goethite on the crown termination of the largest crystal. All crystals are quite clear.

Quartz is a hard silicate mineral composed of silicon dioxide (SiO2) and is one of the most common minerals in Earth's crust. Its piezoelectric property, where pressure creates an electrical charge, makes it essential for frequency controls in everyday devices like cell phones and computers.

Minas Gerais is a Brazilian state whose name translates to "General Mines" and is renowned for its diverse pegmatite minerals, particularly tourmaline, beryl, and quartz from the northwest granitic region. The area is a major global producer of iron ore, gold, and gems, with the Iron Quadrangle serving as a historic source of bedrock gold and a leading district for iron and gem mining. Governador Valadares functions as the commercial center for the state's mineral trade, while localities like the Cruzeiro mine in São José da Safira remain world-famous for tourmaline and specimen production. Collectors today prioritize this region for its exceptional variety of high-quality gemstones and mineral specimens from distinct geological settings.