October birthstone: Iridescent opals to shop this month
The opal is sought-after by admirers for its eye-catching iridescence. Made of tiny silica spheres, it's formed when silica-rich water seeps into the cracks and crevices in the earth’s crust. They are two types of opals: common opals and precious opals. Common opals (as the name implies) are abundant, while precious opals are very rare—both are mainly found in Australia.
The difference between these two types of opals is the spectrum of colours displayed by the stone. Common opals are usually opaque or translucent, with less shimmer and iridescence. Precious opals, however, catch the light and display rainbow-like colours with a prismatic effect that's very captivating.
Unlike most gemstones, opals are amorphous and do not have a defined crystallised structure. Thus, they can be of many shapes and colours. Black opals are the rarest and most prized, as their dark body tone allows the flashes of colour to appear more vibrant and intense.
Opals are one of two October birthstones, the other being tourmaline. For those celebrating a birthday or fans of this iridescent stunner, we've curated a list of opal jewellery—set in yellow or white gold—for you to shop.
Shop them below: