👉 Haidingerite is a mineral formed by the interaction between iron and magnesium. It is a grayish-brown, crystalline solid with a characteristic "haidinger" shape. Haidingerite has a hardness of 12-14 on the Mohs scale of hardness. It is commonly found in the rocks of southern Spain and Portugal, particularly in the areas around the city of Haidinger, near the town of Cava de la Vina.
