Figure 3
Mexico's Cueva de los Cristales (Cave of Crystals) contains some of the world's largest known natural crystals of gypsum (as long as 11 m). `They are the Sistine Chapel of crystallography', according to Juan Manuel García-Ruiz (García-Ruiz & Trueba, 2009). Source: The Giant Crystal Caves of Naica, copyright Madrid Scientific Films 2009, photograph Javier Trueba. |