Crystal opal is a type of opal that is transparent or translucent and has a deep, vibrant colour play. Unlike other types of opal, which have a more diffuse or milky appearance, crystal opal has a glass-like clarity that allows the colours to shine through. Crystal Opals are translucent when held to the light, often having no potch backing. This opal is prized for its unique and beautiful colour display, ranging from deep reds and greens to soft pinks and blues. While Crystal Opal can be found on all Australian fields in some form, the best-known specimens are found in Andamooka, SA.
There are many reasons why someone might want to buy crystal opal. For one, it is a beautiful and unique gemstone prized for its vibrant colour play. Many people enjoy wearing crystal opal as jewellery because it is a striking and eye-catching gem that is sure to attract attention. In addition, crystal opal is a durable gemstone suitable for everyday wear, so it can be an excellent choice for those who want to incorporate a little luxury into their everyday wardrobe. Finally, crystal opal is a valuable investment, as it is a rare and sought-after gemstone that will likely hold its value over time.
Colour
Crystal opal can come in many colours, including red, green, blue, pink, purple, and orange. The exact colour of a given crystal opal will depend on the specific minerals and impurities present in the gemstone and the angle from which it is viewed. In general, crystal opal is known for its vibrant and multi-coloured play of light, which is caused by the diffraction of light as it passes through the gemstone's many internal layers. Because of this, crystal opal is often described as iridescent, meaning it appears to change colour depending on the angle from which it is viewed.
Hardness
Crystal opal is a type of hydrated silica. It is made up of silicon and oxygen atoms that are bonded together and arranged in a specific crystalline structure. This structure gives crystal opal its unique physical and optical properties, including its hardness. On the Mohs scale of mineral hardness, which measures the relative hardness of different minerals, crystal opal has a hardness of 5.5 to 6.5. It is relatively soft compared to other gemstones and can be easily scratched or damaged if not treated with care. It is essential to handle crystal opal gently and store it carefully to prevent damage.
Cut
The typical cut for crystal opal is a cabochon, a smooth, rounded gemstone with a domed top and a flat bottom. This cut is often used for crystal opal because it helps showcase the gemstone's unique colour play and iridescence. In a cabochon cut, the gemstone is polished and shaped into a smooth, rounded dome, which allows light to pass through the gemstone and create a dazzling display of colour. Because crystal opal is a relatively soft gemstone, it is also essential to cut it carefully to avoid damaging the gem. A skilled gem cutter will take special care to cut the gemstone in such a way as to maximize its beauty and colour play.
Value
Crystal opals are generally considered to be valuable gemstones. This is because they are rare and sought-after and have unique and beautiful colour displays that gem collectors and jewellery lovers highly prize. The exact value of a crystal opal will depend on several factors, including its size, colour, clarity, and overall quality. In general, however, crystal opals are considered among the most valuable and desirable gemstones. They are often used in high-end jewellery and are considered a good investment for those interested in purchasing gemstones.
Forming Process
Crystal opal forms in a similar way to other types of opal, which is through a process of chemical precipitation and sedimentation. This process occurs when silica-rich waters, such as those found in underground rivers and hot springs, come into contact with rocks and minerals that contain aluminium, iron, and other elements. Over time, the silica in the water combines with these elements to form opal, which is a type of hydrated silica.
Crystal opal forms when the opal being formed has a high level of transparency or translucency and a deep and vibrant colour play. This occurs when the opal forms in conditions conducive to developing these qualities, such as when the silica-rich waters are free of impurities and the conditions are just right for the opal to crystallize in a specific way. Once the crystal opal has formed, it can be mined and cut into gemstones for use in jewellery.
