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.

The most important bet here is whether money is now flowing into the continent, and if so, whether that will continue. It seems assured that foreign investment will continue. Emerging/frontier market ascendancy has led to huge stock booms in those countries this past decade. Africa would seem to be lining up for the biggest modernization and quality-of-life improvements of any other investment destination.

Unfortunately, there are also social issues, such as violence and corruption, in various parts of Africa that could hinder success or bring objections from some people who take into account social responsibility.

The investment risks are vast. Over a 20-year period (there must be a long-term perspective applied to this theme), there will be booms, busts, bubbles, corruption, wars and other problems as the continent tries to modernize.

In a way, there must also be a short-term perspective applied to this theme. It would not be a big surprise if at some point the fund went on, say, a four-month tear up 50%. When the market offers one of those, it will make sense to sell, or at least reduce the position. A market that can go up 50% in a few months could easily decline just as much just as quickly.

At the top of this article, I joked about yet another frontier market -- but in fact, the dynamics that move Africa will be very different from the dynamics that move the PowerShares MENA Frontier Countries Portfolio ( PMNA), which invests primarily in the Middle East, or the Claymore/BNY Mellon Frontier Markets ETF ( FRN), which is heaviest in Poland and Chile.

I wouldn't be surprised if, six months from now, we see that the correlation numbers of the three are quite low. While I would not allocate more than 4% or 5% to frontier markets in total (I have 1% allocated to Vietnam for a few accounts), I think an investor could allocate to all three without much overlapping effect.

At the time of publication, Nusbaum had no positions in any of the securities mentioned, although positions may change at any time.

Roger Nusbaum is a portfolio manager with Your Source Financial of Phoenix, and the author of Random Roger's Big Picture Blog. Under no circumstances does the information in this column represent a recommendation to buy or sell stocks. Nusbaum appreciates your feedback; click here to send him an email.