Hippopus porcellanusNorthwestern Pacific Though known as Giant Clams, only Tridacna gigas reaches a very large size. The present offering is a large saltwater pearl of exquisite form and with an exemplary flame pattern iridescence. The shape is an exceptional bouton-shape with a high dome, the underside is slightly rounded, yet flat surface with a fascinating starburst effect to the flame pattern iridescence which is even more beautiful due to its high luster. Weighing approximately 15.81 carats and measuring 13.89 x 10.72mm