We were lucky enough to stumble upon an old lot of stones from a dealer going out of business. These stones are natural colored. They are not heat treated or dyed. If you are not familiar with iolite, it is a lovely stone. Iolite is the gem variety of the mineral Cordierite. It describes the transparent to translucent form of Cordierite. Iolite can be light to deep blue. These chips are a darker blue when they are against something and a light blue when they are held up to the light. They are translucent. There is some variation of size of bead within the strand from about 4 mm to thin shards. The strand is 35 inches long and contains approximately 350 beads. Most of the beads are small and have a nice variety of color from very light blue to darker blue with small flashes of purple here and there. Price is per strand; minimum purchase three strands.