Rhodium

Source:http://www.goldeneaglecoin.com/Other_Metals

Rhodium is the 5th precious metal, joining gold, silver, platinum and palladium. The 5 ounce bar shown is on sale for $5,850.  Current spot price per ounce is $1,175.  Only 25 tons of it are mined per year, mostly from South Africa, and almost all of it is used industrially in catalytic converters for automobiles.

The price for Rhodium hit $10,100 per ounce on June 19, 2008 before dropping below $1000 per ounce by the end of 2008.  The price is currently on a downward trend, similar to the other precious metals.

"Rhodium is a non-exchange-traded commodity and because it does not trade on the commodity exchanges it cannot be bought on margin like other commodities. Thus it cannot be bought using futures, exchange traded funds, contracts for differences (CFD’s), spread betting or other derivatives. Rather, investors must opt for the far more conservative and safer route of owning the actual physical metal itself rather than paper derivatives. Rhodium is finite and the rarest of precious metals. In a finite planet with a rapidly growing population and money printing and currency debasement on a scale not seen in modern times, rhodium is likely to at least preserve value in the coming years."
http://moneyweek.com/investing-in-commodities-precious-metals-rhodium-93413/

"“Rhodium is the most price-inelastic of the platinum group metals on both the supply and demand sides of the price equation”. That means that when there is a surplus or deficit of rhodium, the price goes up or down dramatically and hardly balance the market of the metal. ... Rhodium tends to occur along with deposits of platinum and is primarily obtained as a byproduct of mining and refining platinum. That’s why even high rhodium price, doesn’t change the supply, because there is no rhodium mine in the world but mines of platinum.  Rhodium has suffered huge price decline and the downside seems limited. The upside potential is compelling. 
http://octafinance.com/2011/rhodium-investment/