OPAL IS BEAUTIFUL
OPAL is A Mineraloid
Opal is a hydrated amorphous form of silica (SiO2·nH2O); its water content may range from 3 to 21% by weight, but is usually between 6 and 10%. Because of its amorphous character, it is classed as a mineraloid, unlike crystalline forms of silica, which are classed as minerals. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone,rhyolite, marl, and basalt. Opal is the national gemstone of Australia.
OPAL Diffracts Light
The internal structure of precious opal makes it diffract light; depending on the conditions in which it formed, it can take on many colors.
HOW IS OPAL FORMED?
Opal is formed from a solution of silicon dioxide and water. As water seeps through sandstone, it picks up tiny particles of silica. Millions of years ago, the solution flowed into cracks and voids in sedimentary as well as volcanic areas inland Australia. Estimates suggest this solution had a rate of deposition of approximately one centimetre thickness every five million years at a depth of forty metres. Over a period of approximately 1 to 2 million years after this period solidification occurred as the climate changed. The opal therefore remained soft and un-cemented for long periods before becoming hardened
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OPAL is beautiful like the rainbow and all of you beautiful people
Precious opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black.
OPAL