Holy See Birthstone Opal Diamond Fashion 2015 Gold Wedding Jewellery 100032

 Holy See Birthstone Opal Diamond Fashion 2015 Gold Wedding Jewellery. 

By Aamir Mannan. 

A close-up view of striations within opal

Besides the gemstone varieties that show a play of color, there are other kinds of common opal such as the milk opal, milky bluish to greenish (which can sometimes be of gemstone quality); resin opal, which is honey-yellow with a resinous luster; wood opal, which is caused by the replacement of the organic material in wood with opal;[9] menilite, which is brown or grey; hyalite, a colorless glass-clear opal sometimes called Muller's Glass; geyserite, also called siliceous sinter, deposited around hot springs or geysers; and diatomite or diatomaceous earth, the accumulations of diatom shells or tests.