Since the company doesn't need to raise cash, doesn't have a...

Since the company doesn't need to raise cash, doesn't have a particularly large number of shares on issue and there's very little chance of a takeover happening, I don't see the need for a share buyback. It might benefit some of the directors to pump up the share price temporarily, we would need to check their incentive packages.

Furthermore, there's a lot that can go wrong with pearl farming, as the Japanese farmers have sadly discovered. So it makes sense to hold a little cash against a temporary set back. I don't think $16 million or so is an overly large sum for such a contingency.