Drought reveals crystals beneath Pyrenees riverbed

Known as the “diamonds of the Pyrenees,” the minerals have become accessible as water levels fall. However, growing interest among collectors has raised environmental concerns, with conservationists warning that extraction could damage geological formations and disturb the riverbed.

Despite their name, the crystals are not diamonds but transparent calcite, a mineral composed primarily of calcium carbonate. They form inside geodes embedded in sedimentary rock known as poudingue.

Alain Le Jeanne, founder of the local conservation group Citoyens du Gave, reported extensive extraction activity near Pau in September. Collectors sometimes break apart rock formations to retrieve specimens, potentially causing permanent geological damage. The crystals have been known for decades, but unusually low river levels have made them easier to access.