Boulder Opal Pendants in Sterling Silver  

Australian Ironstone Opals Set in .925 Silver Settings

Boulder opal occurs almost exclusively in Queensland, Australia, where it forms within ironstone nodules over millions of years. The opal seams follow natural fissures in the rock, producing the characteristic ribbons and patches of color against dark brown matrix. Cutters shape each stone to preserve maximum opal while keeping enough ironstone to support the gem. This results in organic, freeform shapes that reflect the stone's geological origins. On the Mohs hardness scale, boulder opal rates 5.5 to 6.5, slightly harder than standard opal due to the ironstone component. The dark matrix backing intensifies the play of color, allowing greens, blues, and occasional reds to appear more saturated than they would against a lighter background. Because each pendant contains a genuine slice of Australian outback geology, color placement and pattern vary from piece to piece. SilverRush Style has offered natural gemstone jewelry since 2005. We ship free within the United States and set all stones in .925 sterling silver. Browse the full collection to find a boulder opal pendant that fits your style and budget.