pay rock 含矿岩
Pay dirt \Pay dirt\, Pay rock \Pay rock\, etc.
1. (Mining) Earth, rock, etc., which yields a profit to the
miner. [Western U. S.]
[Webster 1913 Suppl.]
2. a discovery, especially after an exploratory process,
which yields a profit or sought-after benefit; -- used
especially in the phrase ``to hit pay dirt''.
[PJC]