A Geoscience Digital Image Library

DescriptionOpal, SiO2-nH2O (hydrated silicon dioxide), is considered a mineraloid because its structure is not truly crystalline. The chemistry of opal is primarily SiO2 and varying amounts of water from 5%-10% and greater. This water can help geologists determine the temperature of the host rock at the time the opal formed. The gem in this photo is courtesy of: The Jewel Box, Grand Forks, ND.
PhotographerDarla Sondrol. 2002-04-22.
CollectionThe Jewel Box Collection of Gemstones.
Key wordsopal, Jewel Box
Tech details38 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens.
GeoDIL number2737