After spending more than $80 million on the project, the U.S.’s largest gold-mining company has ended plans to open the first major open-pit, cyanide-leach mine in Washington state. The Crown Jewel Mine in northeastern Washington would have blown the side off a mountain to extract about 1.4 million ounces of gold. Houston-based Newmont Mining Corp. said yesterday it had decided that the mine would not return enough to make it financially worthwhile. In the past, former Sen. Slade Gorton (R-Wash.) helped fight off efforts by the Clinton administration to kill the mine — a position that may have contributed to his defeat by Sen. Maria Cantwell (D-Wash.).