sitting on a gold mine

sit on a gold mine

To possess or have access to something that will yield a very large amount of money, especially when that thing has yet to be profited from fully. If your social networking site is attracting millions of new users every month, then you guys are definitely sitting on a gold mine. With its vast stores of untapped crude oil, the small nation state is sitting on a veritable gold mine, but so far it has refused to allow any companies to drill on its land. Each one of those paintings would sell for hundreds of thousands of dollars. You can't just sit on a gold mine like that and not take advantage of it!
See also: gold, mine, on, sit

sitting on a gold mine

Fig. in control of something very valuable; in control of something potentially very valuable. When I found out how much the old book was worth, I realized that I was sitting on a gold mine. Mary's land is valuable. She is sitting on a gold mine.
See also: gold, mine, on, sitting
References in periodicals archive ?
As to whether Co Armagh could literally be sitting on a gold mine, he said: "That's the ultimate goal and what we are hoping for."
You're sitting on a gold mine is supposed to mean you have a great opportunity to become really wealthy.
But the residents could be literally sitting on a gold mine. Traces of the precious metal have been discovered after a geological mapping study of natural resources.
Colombia could be sitting on a gold mine, several of them actually.
"With the creativity of March Productions and the dedication of our team, we're sitting on a gold mine."
As to whether Co Armagh could literally be sitting on a gold mine, he added: "That's the ultimate goal and what we are hoping for."