Common black opal. Narrator: Opal is formed when silica-rich groundwater hardens in rock over millions of years. Large silica spheres within the stone diffract light, creating vibrant colors.

Mineral Monday is a weekly video series exploring the many amazing minerals, fossils, and historic objects on display at the W.M. Keck Earth Science and Mineral Engineering Museum as told by museum ...

Scientists have discovered a completely new type of opal formed by a common seaweed which harnesses natural technology by self-assembling a nanostructure of oil droplets to control how light ...

Press release issued: 17 April 2018 Scientists have discovered a completely new type of opal formed by a common seaweed which harnesses natural technology by self-assembling a nanostructure of oil ...

Opals are a gem known for being a byproduct of lava flow. Hartrim managed to break off the 175-pound chunk of rock he thinks is common fire opal by placing his car jack under the protruding piece ...