Seeds and Nuts
Many different types of seeds and nuts are used as beads. In fact, the very first beads ever used by mankind were most likely nuts and seeds. Nuts and seeds were also a very important food source, perhaps in the gathering and processing of seeds and nuts that lead early mankind to use nuts and seeds as adornment. Some nuts and seeds become incredibly hard once they have matured or dried out. Examples of these are kukui nuts, buri nuts, saluwag and acorns. Maiz or corn dried can make interesting beads and are surprisingly hard once dried.
Is it possible that early necklaces and strung seeds were really just a portable meal waiting to be ground or cooked into eatable food? Whether it was meant for food or adornment, nuts and seeds lent a beautiful organic feeling to the wearer, if a meal can be an added benefit, then all the better.