Another week, another frontier market ETF. Today it is the Market Vectors Africa Index ETF ( AFK).Until now, investing in Africa with an investment product meant a disproportionately large weight to South Africa -- but not so with AFK. South Africa figures prominently at 25%, but Nigeria weighs in at 32% (a combination of 25% of companies actually listed in Nigeria and 7% companies listed elsewhere deriving at least half of its revenue from Nigeria) and is the largest country. Egypt is allocated at 13%, Morocco 11%, Equatorial Guinea at 6% and the rest are too small to move the needle. Not surprisingly, the financial sector is the largest at 33%, since every country has at least one big bank. Basic resources is the second-largest, at 18%, as mining is a significant economic catalyst for many countries. Consumer stocks have almost no representation, so the fund is a bet on the big-picture prosperity as opposed to consumers. Anyone who spends more than a little time researching exotic stocks might recognize a couple of names in the fund like Sassol ( SSL) from South Africa, a couple of the Orascom companies from Egypt and a couple of the mining stocks, but beyond that most of the names will be unfamiliar. AFK holds 50 stocks and charges 0.83%. The info sheet from Van Eck shows no backtest information. This may seem odd at first, but really is not -- the mindset for buying into Africa needs to be much different than deciding on some other sort of investment. More so than with any other theme I can think of, Africa is a bet on the future.