Non nacreous pearl from the “spiny oyster”: 6.97 ct bicolored white and pink Spondylus p

Non nacreous pearl from the “spiny oyster”:
6.97 ct bicolored white and pink Spondylus pearl with a beautiful reflective blue coloration a flame structure when viewed in certain directions under a single white light source. Photo by Robert Weldon/GIA.
The spiny oyster shells occur in reds, oranges and purples depending on their diet. Because of their vibrant colors spiny oyster shells are often used in jewelry; especially Native American jewelry.