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
Trade beads creating powdered glass beads to mimic the appearance of millefiori beads. The success of this form of currency can largely be attributed to the high intrinsic value African people put upon decorative items. Glassmaking was not common in Africa. Africans often used beads for currency (often referred to as african money). and wealth storage, and social status could be easily determined by the quality, quantity and style of jewellery worn. This created a high demand for trade beads in Africa. Trade beads Trade beads (sometimes called aggry and slave beads) were otherwise decorative glass beads used between the 16th and