Platinum has been on a roll recently. Unfortunately for bulls, it's been mostly downhill in June. The October NYMEX delivery topped out at $1,304 an ounce on June 4, then slid more than $140 before finding buying support last week.

Futures opened down today, slipping nearly $3 to the $1,208 level only to sink to a midmorning low of $1,188.

Despite recent wooziness, platinum's turned in a, um, sterling performance for the year. That's been reflected in gains of more than 25% in two exchange-traded notes (ETNs) tracking the metal's price.

And, oddly enough, these competing securities inure to the benefit of a single investment bank.

The E-TRACS UBS Long Platinum ETN (NYSE Arca: PTM), launched in May 2008, got to market first. The E-TRACS note tracks the performance of the UBS Bloomberg CMCI Platinum Total Return benchmark, a fully collateralized basket of platinum futures, targeted for a constant three-month maturity.

Two months after the E-TRACS product debuted, Barclays plc issued notes under its iPath mark that were designed to simulate the return of the Dow Jones-AIG Platinum Sub-index. Subsequent to UBS's purchase of AIG's index unit, the notes were rebranded as the iPath Dow Jones UBS Platinum Sub-index ETN (NYSE Arca: PGM). The iPath benchmark represents a collateralized portfolio of front-month platinum futures.

There are inherent similarities between the two products. Since both are essentially proxies for the nearby futures contracts, their returns are quite similar. Another similarity, created more recently, is the UBS brand.

YTD Performance - Long Platinum Exchange-Traded Notes

With its takeover of the UBS index operation, the Swiss bank now straddles the platinum ETN market. The E-TRACS product, of course, is a direct debt obligation of the firm. With that, investors get a slug of UBS credit risk. The iPath product represents a source of licensing revenue for UBS and presents investors with the counterparty risk of dealing with Barclays Bank.

UBS has another platinum product in its stable - the E-TRACS UBS Short Platinum ETN (NYSE Arca: PTD). With an average daily volume of only 134 notes, though, the market's clearly voted "no" on this security.