Cave of Crystals, Naica Mine, Mexico
^BCave of Crystals.^b Geologist in the Cave of Crystals (^ICueva de los Cristales^i) in Naica Mine, Chihuahua, Mexico. The crystals are the largest known in the world, and are formed of the selenite form of gypsum (calcium sulphate). They formed over millions of years in the mineral-rich geothermally heated water that filled the caves. The crystals were discovered after the water was pumped out of the mine. The Cave of Crystals is 290 metres deep, and was discovered in 2000. Above it, 120 metres deep, is the Cave of Swords (^ICueva^i ^Ide^i ^Ilas Espadas^i), which was discovered in 1912. The crystals in this cave are smaller as its water cooled more rapidly.
© JAVIER TRUEBA/MSF/SCIENCE PHOTO LIBRARY
The Conversion of St. Augustine (tempera on panel)
XIR173406 The Conversion of St. Augustine (tempera on panel) by Angelico, Fra (Guido di Pietro) (c.1387-1455); 22.5x34.5 cm; Musee d'Art Thomas Henry, Cherbourg, France; (add.info.: conversion from a former life of loose living; one of the four latin Fathers of the Church;); Italian, out of copyright
© Copyright: www.bridgemanimages.com
Cave painting, artwork
Cave painting. Artwork of human figures painted on the wall of a cave, including scenes of cooking, drinking, fighting, and social interaction. The oldest known cave paintings date back tens of thousands of years. Typically cave painting pigments included manganese oxide and charcoal.
© SMETEK/SCIENCE PHOTO LIBRARY
Adult, Anthropological, Anthropology, Art Work, Cave, Cave Painting, Cooking, Drinking, Female, Historical, History, Illustration, Male, Man, Pre Historic, Pre History, Socialising, Woman