super dark amethyst geode from Uruguay with calcite flower

A very dark amethyst geode from Uruguay, into whose deep purple inner lining a striking calcite flower has grown. A two-mineral genesis with clear visual contrast.

Amethyst first crystallized in the lava geode from silica-rich solutions over millions of years. Only then did calcium carbonate-containing solutions penetrate the remaining cavity and allow the calcite flower to grow as a second generation. The scalenohedral pyramids of the calcite flower clearly stand out against the purple quartz background.

Uruguayan material from the Artigas Basin provides the most intense amethyst colorations worldwide, with the compact dark purple hue typical of the region.

The combination with calcite scalenohedra is valued in the collector's trade as a didactically valuable multi-generational piece: it makes the sequence of solution phases directly visible on the stone.

A collector's piece with clear mineralogical stratigraphy and visual tension.