The Ocean Blue Sea Turtle Pendant has a special coloring in its shell call Dichroic. It is a specially treated glass that has be fumed in a vacuum oven with a metal such as gold that has been vaporized and heat treated. We don't actually do that part but we use the dichroic glass and submit it in side our blown glass sea turtle shell. The mottled colored head and fins are added afterwards and finished by firing it in an annealing over for about an 8 hour period. We mount them on a pendant cord such as the one pictured. Many who love diving or scuba diving wear our sea turtles and octopus pendants. We also have tentacle pendants, Manta ray pendants and a Sea Horse pendants.