Home » Gemstones » Opal » Boulder Opal

Boulder Opal


Pictures of Boulder Opal


Boulder Opal

Boulder Opal: The bead on the left was cut from Australian boulder opal. It weighs 1.9 carats and measures 10 x 6 millimeters. The specimen on the right is opal in andesite from Honduras. It weighs 2.9 carats and measures 8 x 13 millimeters.

What is Boulder Opal?

"Boulder opal" is a term used for a rough or a cut gemstone that displays opal within its surrounding rock matrix. Opal often forms within voids or fractures in its host rock, and specimens of boulder opal reveal this aspect of opal's origin. The contrast of color can be striking when a bright flash of opal is seen within the surrounding rock material. Many people enjoy the natural appearance of boulder opal and find these gemstones to be beautiful, interesting and educational.




boulder opal

Boulder Opal: This oval cabochon weighs 1.90 carats and measures 10 x 6 millimeters.



More Gemstones
  Diamond
  Pictures of Opal
  Ruby and Sapphire
  Emerald
  Tumbled Stones
  100+ Gems
  Extraterrestrial Gems
  Mined in America

geology store

Find Other Topics on Geology.com:


Rocks
Rocks: Galleries of igneous, sedimentary and metamorphic rock photos with descriptions.
Minerals
Minerals: Information about ore minerals, gem materials and rock-forming minerals.
Volcanoes
Volcanoes: Articles about volcanoes, volcanic hazards and eruptions past and present.
Gemstones
Gemstones: Colorful images and articles about diamonds and colored stones.
General Geology
General Geology: Articles about geysers, maars, deltas, rifts, salt domes, water, and much more!
Geology Store
Geology Store: Hammers, field bags, hand lenses, maps, books, hardness picks, gold pans.
Earth Science Records
Earth Science Records: Highest mountain, deepest lake, biggest tsunami and more.
Diamond
Diamonds: Learn about the properties of diamond, its many uses, and diamond discoveries.