Natural Stone Resources TRVSILVER1224H-5MEPC 12" x 24" 5cm Silver Honed Modern Edge Travertine Pool Coping. Natural Stone Resources is a premier importer & distributor of quality natural stones from around the world. Whether you're looking to add coping to your masonry walls, columns, landscape, steps, or pools, the Silver Travertine Modern Coping is a beautiful choice. This coping provides a smooth surface and acts as a great finishing accent.