Sewant (or siwan) is the black and/or dark purple black shell bead system of the 17th century in Nieuw Nederlandt of what is 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 is equal to two white wampum. The sewant is tied to the stiver, denarius of England (penny or d.), ore, daler, real, livre. 20 stiver = 24d or 1 stiver = 1.2d. Sewant is the Dutch rendering of what the Native Americans in the 1600s of what is now New York, Connecticut, New Jersey, Pennsylvania, Rhode Island, and Massachusetts called the purple and white parts of the Quahog shell when made into beads, used as money and trade between the Dutch, Native Americans, English, French, and other people. The money was of the Dutch money system, and translated into the different European and Native American trade and money systems at the time, around the 1620s to 1660s.