Up for sale is a vintage Tridacna Gigas, or giant clam shell. The largest specimens of these clams ever found were 4 feet, 6 inches long, so this one in comparison is very small and can live over 100 years. These shells are a very rare find. The giant clam lives on flat coral sand and is typically found in the Indo-Pacific. This shell would be ideal for display or unique home décor.