More than one of our readers suggested we highlight this beautifully-shot process documentary about the laborious and precise manufacturing of piezoelectric quartz crystals in the early 1940s.

The magic of crystal formation had already been done by natural processes; all that was needed was a little slicing and dicing. As it turns out, though, quartz is so immensely useful for a ...

Discovered in 1999 inside an abandoned mine in Southern Spain, Pulpí Geode is the largest crystal 'cave' of its kind in the world. But what exactly is a geode and how do crystals form inside them?

Tickets for guided tours of the marble cave will go on sale at 10 a.m. on March 31. The cave features stunning stalactites ...