Two well-formed ruby-red Proustite crystals measuring to 1 cm tall from Freiberg in Saxony, Germany. Crystals of Proustite from this old German mining area are seldom found still with their ruby red colour because the outer surface is usually long since oxidised to an opaque steely grey due to prolonged exposure to light. This specimen must have been hidden away from daylight ever since it was found to remain preserved in this fine, natural condition.