Postcard: £5,293 a gram
The most expensive postcard in the world –sent from a Fulham-based writer named Theodore Hook to himself in 1840 – was sold for £31,758.75 in 2002. Considering its weight, Latvian collector Eugene Gomberg paid more than £5,000 per gram for the world's oldest postcard.
#4 & #7... Not sure what I am missing here.. But it seems that if I grind my solid gold bars up into a fine powder I can increase it's value by 700%.. from $28 to $200 a gram??