A small geological novel carved into matter, that double voice of amethyst and calcite that rarely harmonize so well within the same cavity. This large geode from Uruguay contains an extremely rare internal formation: a primary calcite stalactite that grew millions of years ago from the ceiling of the basaltic cavity and was later partially covered by saturated violet amethyst crystals. This alternation of hydrothermal phases has left a clear imprint in the material: the older calcite emerges as a pale and massive body, while its lower part was colonized by amethyst, which developed its own stalactitic growth following the original structure of the crystal. At a later stage, an additional, more transparent generation of calcite was deposited on top, creating a sequence of layers that reveals the entire history of the geode. The color of the amethyst is typical of Uruguay: deep, vivid, with grape like reflections and hints of indigo. The calcite, on the other hand, retains a more ethereal, almost glacial presence, like a luminous column immersed in a constellation of violet microcrystals.