A "jar of gold" is the big economy-sized jar of mayonnaise that some people keep in their fridge. God only knows what most people would do with such a big jar of mayo, but some people can't seem to get enough. A jar of gold can also be defined as a huge container of "Miracle Whip" which in fact is not really mayonnaise - it's a salad dressing or dip!
Little Boy: What's for supper Mom?

Mom: Sandwiches again!

Little Boy: Oooo! I'll bust out the jar of gold!

Mom: Make sure to get your sister to give you a hand - I don't want you to throw out your back again trying to lift that thing all by yourself!
by wvdrtnsf May 15, 2009
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