Ricardo Marin, former CESPROMIN student,1998-1999,is working at the silver and zinc mine of Naica which is located in Chihuahua state in the north of Mexico. He sent us these few astohishing photographs.

On december 4th, 1999, an exploration drift in development located at 290 level of the mine intercepted a cave full of fabulous samples of selenite, as never seen in the world. Some of these samples are crystals more than 10 meters long and 1.5 meter diameter.

The Naica mine is the most important producer of lead in this country. Mining operations started in the late 1800's and from 1950 up to now, the mine belongs to the Penoles group which is a most important mining operator in Mexico.

The Naica ore deposit is a skarn polymetallic type hosted by cretaceous calcareous sedimentary rocks (limestones) and large faults as the Gibraltar and the Naica faults which are the main canals for large roads of water at 55°C, more tant 30 kg/cm2 pressure and saturated by calcium carbonates and sulphides thus creating a favorable environment for development of crystals of different minerals as selenite, anhydrite, blende and galena