After more then 20 years, I'm still blown away by the mysterious nature of opal. One designer refers to it as the "captive rainbow". One type of opal that is especially fascinating to me is Boulder Opal. No it doesn't come from Boulder, Colorado. Boulder Opal refers to a special type of opal that occurs near Queensland, Australia.
Opal comes in infinite variety but there is one distinctive characteristic of Boulder Opals that gives them away. The presence of the brown ironstone matrix. In the area where these opals occur, there are ironstone formations that have cracks and small fissures. Opal filled those cracks in the form of a silicate gel which eventually hardened into brilliant crystalline opal. When cut from the rock with a natural backing of the dark colored ironstone, these opals flash with incredible colors. Also, boulder opals typically have an irregular surface where they were broken open along the seam of opal.
Even the thinner and sparcer seams of opal can be intriguing. Some boulder opals are more matrix than they are opal, but the colorful flash of opal peaking out through the brown ironstone is fabulous. Here is a particularly unique pendant we recently received that is sculpted to include both the beautiful patterns of the ironstone and a strong color seam of opal. The jeweler who created the mounting got extra creative and her freeform gold setting looks like something from the Jetson's. As usual, photos don't do these things justice, so if you can, stop by the gallery and I'll show you all the wonderful Opals we have on hand. Or click here to see a small selection on our website.