October Birthstone: Opal
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OPAL

October’s birthstone, the opal, symbolizes faithfulness and confidence. The word comes from the Latin opalus, meaning “precious jewel,” and from the Greek word opallios, meaning “to see a change in color.” Discover more about this month’s birthstone!

Opals are a type of quartz made up of tiny spheres of amorphous hydrated silica, which give it its rainbow shimmer.

Opal’s high water content makes it prone to cracking or crazing (many fine cracks), however. This can happen if the gem dries out, such as might occur when exposed to high temperatures or long periods of low humidity. The gem is relatively soft, with a hardness rating of only 5.5. (Never place an opal in an ultrasonic jewelry cleaner: The vibrations can crack the gem.)
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October’s birthstone, the opal, symbolizes faithfulness and confidence. The word comes from the Latin opalus, meaning “precious jewel,” and from the Greek word opallios, meaning “to see a change in color.” Discover more about this month’s birthstone!

Opals are a type of quartz made up of tiny spheres of amorphous hydrated silica, which give it its rainbow shimmer.

Opal’s high water content makes it prone to cracking or crazing (many fine cracks), however. This can happen if the gem dries out, such as might occur when exposed to high temperatures or long periods of low humidity. The gem is relatively soft, with a hardness rating of only 5.5. (Never place an opal in an ultrasonic jewelry cleaner: The vibrations can crack the gem.)
The October birthstone is the opal … or possibly tourmaline, depending on your source. Opals are the most well known birthstone for October. They are amazingly diverse rocks, taking on different appearances depending on how they formed. Precious opals, known for their flashy iridescent colors, are popular in some jewelry. But even the less dazzling common opals possess a quiet beauty that makes them popular as specimen collections.

Unlike most other gemstones, opals do not qualify as minerals in the usual sense. They contain myriads of tiny silica spheres in a tightly-packed lattice. These gemstones, famous for their “play of colors,” flash rainbow hues when moved, due to the interference of light with their internal structures.

Opals form in near-surface volcanic rocks, within cavities and cracks. In sedimentary volcanic ash rock, percolating water in the ground dissolves silica that eventually precipitates to form the opal. On rare occasions, it becomes the replacement material for fossils – shells, bones, wood – whose original material had dissolved away.
Opal is a unique and popular gemstone which lends itself beautifully to jewelry, amongst many other things. Have you ever seen the way an opal’s many colors shine? Read on, and we’ll discuss five weird and cool facts about the popular October birthstone, the opal!

Many believe that opal forms when rain becomes trapped inside of a rock. The rain carries the rock’s crystalline silica downwards. Then, the silica eventually dries out.

In the year 2008, NASA made a very interesting discovery. Opal deposits were found on the planet Mars!

Approximately 95% of the world’s precious October birthstone comes from down under. Opal has been mined in Australia since the year 1875!

Both Ancient Greeks and Romans had specific beliefs about the opal gem stone’s special powers. In Ancient Greece, many people thought that opal could make you psychic! While in Ancient Rome, the popular gemstone was synonymous with hope and love
The varying colors you see in an opal gemstone are a result of the massive amount of diversely sized silica spheres. The spheres cause light to refract and thus create the many different colors on display in the beautiful October birthstone.
The name of this, the traditional October birthstone, is believed to have originated in India (the source of the first opals brought to the Western world), where in Sanskrit it was called upala, a “precious stone." .” In ancient Rome, this became opalus. Most opals are valued for their shifting colors in rainbow hues – a phenomenon known as “play-of-color.”

The October birthstone’s dramatic play-of-color has inspired writers to compare it to fireworks, galaxies and volcanoes. Bedouins  once believed opal held lightning and fell from the sky during thunderstorms. Ancient Greeks thought opals bestowed the gift of prophesy and protection from disease. Europeans long maintained opal to be a symbol of purity, hope and truth. Hundreds of years ago, opal was believed to embody the virtues and powers of all colored stones.

Opal is also the stone given to celebrate the 14th wedding anniversary.
Opal is an original modern birthstone for the month of October. Some people call it the world's most colorful gem because one stone can display a full spectrum of colors. Opal occurs many different varieties. The accompanying image is a black opal from Australia, but there are also fire opals from Mexico, honeycomb opals from Ethiopia, and colorful common opals from Peru. Lab-grown opals are available in a wide variety of colors and appearances for people who would like to obtain an attractive item for a lower price. Lab-grown opals are being sold today in many jewelry stores. Image copyright iStockphoto / mikheewnik.
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