This unusual gemstone is chert breccia. Hand set into a sterling silver mount and highly polished, it is full of colour and texture. This particular stone is classed as a mineral. Breccia forms where broken, angular fragments of rock or mineral debris accumulate. One of the most common locations for breccia formation is at the base of an outcrop where mechanical weathering debris accumulates. Another is in stream deposits a short distance from the outcrop or on an alluvial fan.stone natural chert breccia material 925 solid silverapprox pendant size 33mm x 30mm beautiful gemstones designed by naturethe henryka designer gemstones collection is a celebration of completely natural and beautifully rare gemstones from across the world.each gemstone is carefully hand chosen by us for its natural and un treated colours and patterns. We look for vibrant gemstones we know you will love, as well as rare gemstones you may have never even heard of from all corners of the earth.instead of seeking perfection, we choose gemstones based on the natural quirks and inclusions that make them entirely unique. This means incredible stripes, bold spots, wave like ripples and swirls that give each gemstone its own unique fingerprint.these characterful gemstones are then cut, polished and set by hand into silver jewellery designs, from statement necklaces to rings, earrings and bracelets. When wearing a piece of henryka designer gemstone jewellery, you can be assured that no one will ever be wearing the same piece. It is individual to you.