Beautiful dark amethyst geode from Uruguay

A dark amethyst geode from Uruguay, with particularly deep violet-blue crystal coloration. At 19.1 kg in weight and 40 cm in height, this is a well-balanced collector's geode with premium color depth.

Amethyst is the violet variety of quartz. The coloration is caused by embedded iron trace elements, which form color centers under natural radiation exposure. Uruguayan material is characterized by a more compact, darker blue hue, which is considered the benchmark for premium amethyst in the international mineral trade.

The geodes of the Artigas Basin formed in volcanic cavities of the Serra Geral Basalt Formation. Over millions of years, the amethyst crystals grew in these closed cavities under constant geothermal conditions.

The depth of coloration visible here is an authenticity marker for undisturbed growth: frequent pressure or temperature fluctuations during crystallization result in light zonations or streaks. A homogeneous dark violet coloration, as on this geode, is an indicator of stable deposit conditions.

A collector's item with clear Uruguayan provenance and a calm, deep color presence.