Opal is From?
It just so happens that approximately a dozen distinct classifications of minerals with hundreds of varieties exist in Mexico. As an example, the silicates class alone, contains more than 60 different minerals such as jadeite, zircon, topaz, and quartz, a subgroup of which includes amethyst. The carbonates class consists of bismutite, calcite, magnetite, dolomite, etc. while the sulfates class has gypsum, barite, cuprotungstite, etc.; many of these minerals being used for industrial applications. Finally, the mineraloids class which contains amber, obsidian, and opal; minerals that are frequently carved, ground, cut, and polished for objects of art, jewelry, etc.
Many of these minerals, including most opals, were formed during the Cretaceous period and brought to the Earth’s surface during the Pleistocene age. Of the 25 or so varieties of opals, the fire opal is the only naturally faceted opal and the most significant fire opal deposits are found in Mexico. One of the two largest sites for mining the Mexican fire opal, which just so happens to be the “national gemstone of Mexico”, is located near Magdalena, Jalisco; a small city located approximately 100 miles east of Vallarta that can be visited from PV during one of the ten hour day tours. Magdalena is in a region laden with igneous rocks, obsidian, volcanic lava, and more than 300 opal mines.
Mexican fire opals consist of silicon dioxide or silica spheres arranged in an orderly pattern with iron oxide dispersed throughout. It’s the iron oxide that gives the Mexican fire opal its distinctive brilliant flame-like colors of yellow, orange, and red. The three most important attributes of the fire opal are body colors, transparency, and play of color (differing colors when viewed from various angles). The greater the play of color, the more precious the gemstone. Because most opals are not faceted, they are generally displayed in the cabochon form. However, since fire opals are often found naturally faceted, they can be cut, polished, and mounted as cabochons or faceted stones.
The word opal was derived from the Roman word opalus (to see a change of color) as they popularized the opal around 100 BC and prized this gemstone above all other precious stones believing the holder to be charmed with good fortune. The Mexican fire opal, sometimes referred to as cherry opal, precious fire opal, sun opal, girasol (Spanish for sunflower), and Quetzalitzlipyollitli (gemstone of the bird of paradise) by the Aztecs, was used by the Mayas and Aztecs during the past millennium for ritualistic purposes and in various mosaics. Today, connoisseurs say that fire opals bestow courage, stamina, will-power and energy on the wearer; the warm, fiery orange-red colors are said to have a positive effect on the psyche and convey a profound sensation of warmth, peace and harmony.
Opal is the lucky stone of those born under the Aries sign and it is the birthstone of Libras.
Opal love to be worn on the skin
Due to the differing percentage of water, Opals may easily become brittle. They always contain water – usually between 2 and 6 per cent, but sometimes even more. Thus if stored too dry or exposed to heat over a longer period of time, Opals will show fissures and the play of colour will become paler. Therefore, Opal jewellery should be worn as often as possible, for then the gemstone will receive the needed humidity from the air and from the skin of its wearer.
Opals are not very hard: they only achieve 5.5 to 6 on the Mohs’ scale. Therefore they appreciate a protective setting. In earlier days Opal’s sensitive surface was often oiled, but today also sealing them with colourless artificial resin has become quite popular.