California State Mining And Mineral Museum Mining was the area's primary business through the years till 1985, when the Homestake Mining Company closed down the Bulldog Mine. Admission to the Bon Ami Mine is $eight.00 for adults, $7.00 for seniors over 60, and $6.00 for students. A 12-web page https://zane4y7y6.affiliatblogger.com/54710580/study-shows-surface-coal-miners-are-exposed-to-toxic-dust-that-causes-black-lung