Sewant (or siwan)'s the black and/or dark purple black shell bead system of the 1600s in Nieuw Nederlandt of what's currently the States of New York, New Jersey, Pennsylvania, Connecticut, and Delaware. This fiat currency system was introduced to the English at Plymouth Colony Plantations in 1627. One black Sewant's equal to two white wampum. The sewant's tied to the stiver, denarius of England (penny or d.), ore, daler, real, livre. 20 stiver = 24d or 1 stiver = 1.2d.… (More on Sewant)