RAB held/holds a lot of mining shares in its Mining Fund. The situation is simple: if the fund goes bust, then the shares need to be sold. RAB stated that it could take three years, since many of its holdings are in illiquid stocks.

Try selling only 1,000,000 stocks in any junior miner. If you do that on one single day, the stock plummets and you'll sell at a terrible price. That's the risk when buying illiquid stocks.

Then again, long run, the fundamentals shall overcome.