What is Opal?
Opal is a one of a kind gemstone celebrated for its mesmerizing play of color, which displays a spectrum of hues that seem to dance within the stone. Composed of hydrated silica, opal contains water molecules within its structure, giving it a unique and captivating appearance. With a hardness of 5.5 to 6.5 on the Mohs scale, opal is relatively soft compared to other gemstones, making it more suitable for jewelry that receives less wear, such as earrings and pendants.
Uses of Opal
Opal is a versatile gemstone that has been cherished for centuries. Its primary use is in jewelry, where it is fashioned into rings, necklaces, earrings, and bracelets. Its unique play of color makes it a popular choice for statement pieces and artistic designs. Beyond adornment, opal is also used in metaphysical practices. It is believed to enhance creativity, emotional expression, and spiritual insight. Additionally, opal is sometimes used in decorative items and carvings due to its unique beauty.
The Origin of Opal
Opal is found in various parts of the world, with significant deposits in Australia, which is the largest producer of this gemstone. Australian opals, particularly those from Coober Pedy and Lightning Ridge, are renowned for their quality and vibrant play-of-color. Other notable sources include Ethiopia, Mexico, and Brazil. In the United States, opal can be found in Nevada and Idaho. The gemstone forms in sedimentary rocks, often in areas that were once rich in geothermal activity.
Different Colors and Their Prices
Opal is renowned for its wide range of colors and patterns, each unique to the individual stone. The most valuable opals are those with a vivid play of color and a dark body tone, known as black opals. White opals, with a lighter body tone, are more common and generally more affordable. Fire opals, which are typically orange or red, are also highly prized. Prices can vary significantly based on color, pattern, and overall quality.
White Opal: $20 to $200 per carat.
Black Opal: $500 to $10,000+ per carat.
Fire Opal: $50 to $500 per carat.
Properties of Opal
Opal is not only beautiful but also possesses several intriguing properties. Its play of color is caused by the diffraction of light through the microscopic silica spheres within the stone. Opal has a relatively low hardness, making it more susceptible to scratches and damage compared to other gemstones. It is also known for its water content, which can range from 3% to 21%. This makes opal sensitive to extreme temperatures and dehydration, requiring special care to maintain its beauty.
Treatments of Opal
To enhance its appearance and durability, opal often undergoes various treatments. One common treatment is the application of a clear resin or oil to fill surface cracks and enhance the stone's clarity. Another method is smoke treatment, used to darken the body tone of white opals, making the play of color more pronounced. It's important for buyers to be aware of these treatments, as they can affect the gemstone's value. Always purchase opal from reputable dealers who disclose any treatments the stone has undergone.
