As of the End of 2004, total palladium mined was estimated at 3,781.5 tons. Given annual production is now around 222 tons pa, total mined in human history at the end of 2009 would be around 4,890 tons.
It's hard to believe, but if all the gold ever mined was weighed, it would amount to between 140,000 and 160,000 tons. That would be a cube of approximately 62 feet on a side. A cubic inch of gold...