Uv Beads 50 Pack

These low cost solar beads (UV beads) are extremely sensitive to natural light and change colour dramatically from white to various colours when taken outside - even on an overcast day. Containing trace amounts of a photochromic pigment that responds the the ultraviolet component of daylight, the beads have many different uses ranging from scientific testing of (UV) sun block materials to the creation of 'smart' jewellery. Includes 10 each of 5 colour variations, 50 beads total.