That is left to the lucky miner who by chance finds the run on his claims.

http://www.thefreedictionary.com/run
n
........
16. A pipe or channel through which something flows.
17. Eastern Lower Northern U.S. See creek.
18. A fall or slide, as of sand or mud.
19. Continuous length or extent: a five-foot run of tubing.
20. Geology A vein or seam, as of ore or rock.
22.
a. A trail or way made or frequented by animals.
.....

выдумки, наверное, но люди говаривают о волшебной силе контекста .... хотя, кто знает - может кому и правда помогло