Open Amethyst Geodes from Sonora, Mexico feature small double terminated amethyst crystals and druzy inside a pale pink and white matrix. These are already open geodes with sizes ranging from 4 - 7 cm in length.

Price is for one open geode piece, number of larger inner crystals will vary between each piece. Its chemical formula is SiO₂ and owes its purple coloration to irradiation of ferrous iron: Fe³⁺.