Blue fire opals are striking gemstones that flash all the colors of the rainbow. They are made of small spheres of hydrated silica; silica is the component of sand that makes sand! As they form, tiny water droplets are trapped in a grid of spheres in an irregular pattern. The water bends the light passing through the gem, resulting in the magical play of colors, known as opalescence, that this gem is known for!
However, not all opals are created equal! There are four broad categories of opal, white, black, boulder and crystal, which differ in their translucency and the color of the host rock. They also show varying levels of opalescence. And although fashion dictates the changing popularity of individual types of opals, certain types of opals are more suited to some forms of opal jewelry than others. So which form goes best with which piece of jewelry?
They have a milky white appearance that can range from almost opaque to translucent. The more milky the background of the host rock, the harder it is to see the flashes of fiery opalescence within. Their beauty is best seen in strong direct light. Their pale appearance and relative affordability means they are often set as cabochons in silver metal for everyday jewellery.
Black opal necklace silvers are the rarest, most sought after and most expensive form of gemstone. The dark host rock is usually black, blue, brown or gray and provides the perfect background against which to see the gorgeous color display of these gems. They have the appearance of an angry storm cloud behind a rainbow.
They are usually set as cabochons. And they're dramatic enough to hold their own alongside diamonds in statement jewelry, such as a gorgeous anniversary pendant or engagement ring.
Boulder opals are always cut with a portion of the host rock attached. They are typically set in jewelry as thin segments or as baroque stone shapes. They are unusual and extremely attractive pieces that will attract comments and admiring glances! They cannot be easily set into rings, but they make wonderful pendant necklaces.
Crystalline opal types, such as fire opals, are transparent and usually have good clarity that allows strong diffracted color to be seen. This is the only category of gemstone that is usually faceted before being set into jewelry. Fire opals have little opalescence, but are valued for their color instead. They make beautiful rings, earrings and pendants.
