Heavy Metal Seed Beads are made entirely of metal, starting out with a brass base, and then the various highly durable finishes are added. They are very uniform in size and are a much more rounded bead compared to the Japanese glass beads which are generally more cylinder shaped. Due to their shape they can be especially handy for projects that require the beads to snug up against each other, for a close fit. These seed beads are a definite advantage in many designs. They are available in several different metal finishes. Remember, they are all metal, and the edges can be more severe than glass beads. We recommend using Fireline or similar stringing material. Beading threads, such as C-Lon or Nymo are not a good choice of stringing material to use when constructing projects made mostly out of these beads.