pay dirt, hit
Also, strike pay dirt. Make a valuable discovery or large profit, as in We've been researching the source of that quotation for a month and we finally hit pay dirt in the Library of Congress. This idiom, from the mid-1800s, refers to a miner's finding gold or other precious metals while sifting soil. By the late 1800s it had been transferred to other lucrative discoveries.
Words nearby pay dirt, hit
pay back,
pay bed,
pay cable,
pay court to,
pay dirt,
pay dirt, hit,
pay down,
pay envelope,
pay for,
pay grade,
pay in