The following passages are from Dr. Raphael's book Jews and Judaism in the United States: A Documentary History (New York: Behrman House, Inc., Pub, 1983), pp. 14, 23-25.
"Jews also took an active part in the Dutch colonial slave trade; indeed, the bylaws of the Recife and Mauricia congregations (1648) included an imposta (Jewish tax) of five soldos for each Negro slave a Brazilian Jew purchased from the West Indies Company. Slave auctions were postponed if they fell on a Jewish holiday. In Curacao in the seventeenth century, as well as in the British colonies of Barbados and Jamaica in the eighteenth century, Jewish merchants played a major role in the slave trade. In fact, in all the American colonies, whether French (Martinique), British, or Dutch, Jewish merchants frequently dominated.