CANCER (June 21-July 22): In the mid-19th century, prospectors mined for gold in the western Nevada mountains. The veins weren’t as rich as California ones, but some could earn a modest living. Their work was hampered by a gluey blue mud gumming up their machinery. It was regarded as a major nuisance. On a hunch, one miner took a load of the blue gunk to be analyzed by an expert. He learned it contained rich deposits of silver. So began a silver mining explosion that made many prospectors quite wealthy. Be alert for a metaphorical version of blue mud in your sphere: an “inconvenience” that interferes with your treasure-seeking, but is actually valuable.