Great dark and large amethyst geode

A dark amethyst geode from Uruguay in a distinctive columnar shape. Slender vertical geometry with concentrated premium color, the deeply saturated purple hue indicates high iron enrichment in the original crystallization cavity.

Uruguayan amethyst is considered the darkest, most deeply violet-colored amethyst variety worldwide. The strong color results from iron substitutions in the quartz lattice. Deeply dark pieces indicate high iron concentration in the original solution.

The narrow columnar geometry followed the cavity's course in the natural geode. Such columnar geodes are a deposit-specific shape variant in Uruguayan material with its own staging profile.

The deposits in Artigas and Salto supply the premium material from the Arapey Basalt Formation. Columnar shape plus premium color is a double collector's classification for classic display staging.

The Arapey Basalt Formation was formed around 130 million years ago during the breakup of the South Atlantic. Volcanic gas cavities in the lava flows formed the geodes in which the amethyst columns grew over millions of years.

A Uruguayan collector's item with columnar geometry and premium color. Such pieces have their own classification in the international collector's market and are traded with their own price category compared to standard Brazilian geodes. The narrow columnar shape is suitable for display in confined spaces and remains fully legible from a frontal view.