Kwase u Sha Uika was a rare form of marriage among the Tiv in which a man purchased a woman who had been sold into slavery and made her his wife. Because of the high cost involved, this form of marriage was generally limited to wealthy individuals. Unlike other Tiv marriage systems, Kwase u Sha Uika usually involved women from neighbouring ethnic groups rather than Tiv communities. Although it existed historically, it was never a common form of marriage and gradually disappeared with the abolition of slavery and changes in social and legal systems. Paul Bohannan's study of the old Tiv economy explains why such marriages were rare and costly. Slaves, cattle, brass rods and the prestige cloth tugudu belonged to a "prestige" sphere of exchange, above everyday market goods such as food, pots and tools. A man had to have accumulated wealth in that sphere to buy a wife in this way. A purchased wife came without kin in Tivland, which made her position in the household quite different from that of a wife given in exchange.