Opal is the product of seasonal rains that drenched dry ground in regions such as Australia’s semi-desert “Outback.” It is known for its unique display of flashing rainbow colors.

Opal is the product of seasonal rains that drenched dry ground in regions such as Australia’s semi-desert “Outback.” It is known for its unique display of flashing rainbow colors. Gem Encyclopedia

Opal is known for its unique display of flashing rainbow colors called play-of-color. There are two broad classes of opal: precious and common. Precious opal displays play-of-color, common opal does not.

Discover the meaning and history of opal, an October birthstone, and where it can be found.

Consider the opal’s symmetry, thickness, polish, sizing and calibration. Opal Colors. Opal hues can range across the spectrum. An opal might display a single color, two or three colors, or all the colors of the rainbow. Opal displays background color in addition to play-of-color.

2013年10月15日 · The October birthstone, opal, is noted for its individuality, magic, and mystery. Learn why it's flashing rainbow colors is unlike any other gem.

Opal and tourmaline are the two birthstones for October. Both of these gemstones are known for their endless color combinations. Learn more about these two birthstones for October and discover their meanings and where they can be found.

Opal flashes colors as you turn the stone or move around it. This phenomenon is called play-of-color . An opal might show a single color, two or three colors, or all the colors of the rainbow!

2017年1月24日 · Boulder opal is becoming more and more popular. Australia’s central Queensland is the home of more than a dozen of sources of this stone. Come with GIA field gemologists to find out more about this unique gem.

GIA’s Gem Encyclopedia is a virtual journey through the science and lore of gemstones from across the globe. Each precious stone page features additional detailed gemological information, a buyer’s guide, photos, videos & research.