Opal is one of the most unique gemstones in existence and is surrounded by a number of myths & lore! No two opals are exactly alike and this glorious gem used to be considered the most valuable stone until the leaders of the Diamond industry began to spread false rumors during medieval times! The myth that it is "bad luck" to wear an opal if it is not your birthstone was in fact created by commercial diamond dealers and as the general population latched on to the belief, opals decreased in value and diamonds rose to the top. It was all a ploy by big business leaders to get their product recognized as the best! Opals are divided into two categories, common and precious. Common opals have a milky or pearly luster. Precious opals display what is called "play of color" or opalescence. The color flashes that you see in an opal are caused by the diffraction of light across microscopic spheres of silica that make up the opal. Different size spheres in the stone reflect different colors of light. Until recently, almost 90% of the world's opal was mined in Australia. Ethiopian opal is the now the second main source being mined in abundance.
Some types of Opal:
"Australian Opal": Both precious white and blue opal are mined in Coober Pedy and Lightning Ridge Australia. Some of the most valuable opals in the world are found there.
"Boulder Opal": This type displays visible Opal that forms within the fractures and spaces of a host rock (usually sandstone or basalt) and is found in Mexico and Australia
"Pink Opal": A common opal found in Peru; ranges from Pink to lilac color.
"Ethiopian Opal": Precious, fire and common opal are all mined in Ethiopia. Most have a base color that is earth tone from brownish red to light cream.
"Louisiana Opal": Mined in Vernon Parish, Louisiana, fragments of Opal formed alongside Quartz in a brown-blackish matrix of sandstone. It was mined only in the late 1980's and early 90's and is difficult now to find. (Interesting fact: Agate is the Louisiana State mineral... go figure!)
Although different types of opal are connected with different healing properties, generally opal that displays a full color spectrum can aid with balancing all of the chakras. It offers emotional protection and purification and can support all types of physical healing. Opal is the birthstone for October as well!