You get the exact one shown about 42 mm long including bale x 27mm The bail is 4 mm wide x 7 mm tall Silver Plated bale & Bezel Comes with 24" stainless steel ball chain the measurement in mm is the length including the bale US penny is 0.75 inches (19 mm) in diameter. (1" = 25.4 mm) Ammonites are an extinct group of marine invertebrate animals the ammonoid cephalopods first appeared in the Devonian (circa 400 million years ago) & became extinct at the close of the Cretaceous period. It is thought by some that they evolved from the older nautiloids. During their evolution three catastrophic events occurred. The first during the Permian period (250million years ago), only 10% survived. They went on to flourish throughout the Triassic period, but at the end of this period (206 million years ago) all but one species died. Then they began to thrive from the Jurassic period until the end of the Cretaceous period when all species of ammonites became extinct. The name comes from its appearance: it resembles a ram’s horn. in Egyptian mythology, the God Ammon looked like a man with horns like a ram. The ancient fossil was considered Ammon’s stone, thus inheriting the name, Ammonite. Silver Ammonite Nautiloid Fossil Pendant Necklace Jewelry With 24" Chain 6175K
