Founded mainly to trade stock of mining companies, it began operations in 1897 and closed 94 years later on May 24, 1991.

[1] Founded mainly to trade stock of mining companies, it began operations in 1897.

[4] After failed attempts by the board to find an investor or buyer, it closed on May 24, 1991.

[1][4] The exchange closed "because of slumping silver and gold prices and waning investor interest."

[4] At the time of its closure, it had a reputation as a haven for trading speculative penny stocks,[2][5] almost exclusively in mining metals stocks of the Silver Valley in nearby north Idaho.