Shell money most valued by the Native American tribes of the Pacific Coast from Alaska to northwest California was "Dentalium shell", a species of long narrow marine shelled mollusk, a tusk shell or scaphopod. The tusk shell is naturally open at both ends, and can easily be strung on a thread. This shell money was valued by its length rather than the exact number of shells; the "ligua", the highest denomination in their currency, was a length of about 6 inches. Farther south, in central California and southern California, the shell of the olive snail "Olivella biplicata" was used to make beads
Prehistoric beads in the Philippines land mass. Shell beads in the Philippines are generally either whole or cut. Various sites have been found to contain shell beads, including Sucgang Barrio in Bohol; Sibale Island, near Surigao; Suluan island, south of Samar; Lagen Island in Palawan; and Camotes Islands. Various studies have been conducted on these shell beads. Studies on the method of cutting, use, location and whether these were taken whole or broken apart were used as characteristics to define these shell beads. It is also of note that shell beads are of different characteristics throughout the archipelago of the Philippines. Research shows that most