The blood-pumping organ of a greedy/selfish
moocher/fortune-hunter who only yearns for gold; i.e., his
main goal in life is to be given money to either
hoard or spend frivolously.
In the 1937 comedy-film "
Way Out West",
Laurel and Hardy play a couple of witless buddies who unknowingly deliver a deed for a gold mine to the wrong woman; the recipient is actually the
heiress's devious guardian with a "heart of gold"... Laurel naively "hits home" by telling her, "Now that you own a mine, I bet you'll be a swell gold-digger".