Very beautiful dark amethyst geode pair with calcite flowers

A dark amethyst geode pair from Uruguay, whose purple internal lining is accented by light calcite "flowers". The two-mineral genesis is visually clearly discernible.

Amethyst crystallized in the original lava geode from silica-rich solutions. Only after this growth cycle did calcium carbonate-containing solutions penetrate the remaining cavity, allowing the calcite "flowers" to grow as a second generation.

Such multi-generational geodes are relevant to collectors: they document the geological activity sequence of a single cavity structure over long periods. Changes in solution chemistry typically follow tectonic or thermal activity phases.

Uruguayan material from the Artigas Basin traditionally provides the most intense amethyst coloration. The combination with accompanying calcite scalenohedra is valued in the collector trade as a didactic premium piece.

A collector's item with clear mineralogical stratigraphy.