This ring is founded on a thick 10mm wide yellow gold foundation featuring a solid gold reticulated arch design, accented with inlaid crushed ammolite nacre spanning flanking inset circlets of 6,500 year old Morta bog wood or Mammoth tusk ivory. Ammonites are an extinct group of cephalopods that entered the fossil record 400 million years ago; the shells of ammonites develop an inner layer known as the nacre or "mother of pearl" which remains intact in some of the fossils of these extinct animals. The biologically produced components of this design are derived from extinct species which renders them irreplaceable.