An exclusive grey amethyst collection Grey wine-colored amethyst with calcite on chalcedony matrix – Uruguay - Height: 287 mm - Width: 170 mm- 4128 g

A fascinating and rare specimen in its hue: a gray-violet amethyst, with subdued brown and purple shades, developed in a botryoidal form and covered by a very fine druse of microcrystals that gives the surface a diffuse, almost sugary brilliance. The color, unusual and sought-after, is typical of those Uruguayan cavities where the presence of iron oxides and growth conditions have muted the classic violet, resulting in deeper, earthy, and more complex tones. Over this uniform texture, numerous naturally formed rhombohedral calcite crystals stand out, well-formed, dotting the entire surface with small ivory-colored geometries. These are late-stage crystallizations, generated when the hydrothermal fluids inside the cavity began to cool and the pH changed, favoring calcium carbonate precipitation. The side section reveals a matrix of gray chalcedony, with bands accompanying the transition from the outer basalt wall to the richly mineralized inner cavity. It is the typical signature of geodes from Paraná (Uruguay), formed in ancient gas bubbles trapped within Cretaceous basalt flows, later slowly filled by silica-rich fluids and minerals. The overall composition is a balance of matter and color: the gray-violet amethyst, the very fine druse, the milky calcite crystals, and the bands of chalcedony. A collector’s specimen that combines aesthetics, mineralogy, and a geology narrated in every detail of its structure.