The IMF Working Papers series is designed to make IMF staff research available to a wide audience. Almost 300 Working Papers are released each year, covering a wide range of theoretical and analytical topics, including balance of payments, monetary and fiscal issues, global liquidity, and national and international economic developments.
This paper provides an overview of diamond mining in sub-Saharan African countries, and explores the reasons for substantial differences in their tax rates and fiscal revenues from the sector, which mainly arise from differences in the incentives for smuggling. In a theoretical model, we show that optimal diamond tax rates increase with the degree of competition among diamond buyers, as well as with the corporate share of diamond production, which is confirmed by the data. We then discuss policies to increase revenue, including by enhancing mining productivity, stimulating the exploration of new areas, reducing barriers to entry, and attracting investment into value-adding downstream operations.