Beautiful amethyst geode with a great agate rim from Uruguay

A Uruguayan Amethyst Geode with a pronounced agate rim, a classic two-layer stratigraphy from the Arapey Basalt Formation. Violet crystal tips framed by banded chalcedony.

Uruguayan amethyst is considered the darkest, most deeply violet-colored amethyst variety worldwide. The deposits in Artigas and Salto supply the material from the more than 130 million-year-old Arapey basalt layer.

The agate rim documents the first mineralization phase. Before the main amethyst phase, microcrystalline chalcedony aggregates crystallized on the geode's inner wall. The banding lines of the agate rim vary in color and thickness; each variation documents a specific geochemical phase.

The polished cut surface vividly highlights both mineralization layers, making the piece an expressive display element.