And most importantly it is one of the few actual assets which exhibit wild price swings.
All of the Platinum metals seem to exhibit wide price swings. These charts from
a report by the U.S. Geological Survey show long term price trends. Red line is inflation adjusted.
Ruthenium went from $13/oz average in 1993 to $574/oz average in 2007. In 13 years, Iridium fell from $666/oz to $47/oz.
To be honest though, we're really too narrow-sighted when we look at a mere forty years in these metals. Trends can emerge over very long time periods indeed, and what can appear as randomness on one scale can be a pattern on another.