Botswana Exports of coke, semi-coke of coal, of lignite, of peat; retort carbon to Zambia was US$1.42 Thousand during 2018, according to the United Nations COMTRADE database on international trade. Botswana Exports of coke, semi-coke of coal, of lignite, of peat; retort carbon to Zambia - data, historical chart and statistics - was last updated on May of 2024.