Dashington trade; 5 Pounds-flat Cobalt Glass Marbles for Vase Filler, Table Scatter, Aquarium Decor Dashington's&trade; High Quality Decorative Smooth Glass Marbles Perfect for aquarium use! Use this item in vases for filler! Looks great spread around centerpiece! Size is approximately 3/4" 5 pound bag contains approximately 400-500 marbles