31. The deposit is currently under development by Cradle Resources to mine niobium by open pit mining methods. 32. Uranium mining declined with the last open pit mine shutting down in 1992 ( Shirley Basin, Wyoming ). 33. Uranium mining declined with the last open pit mine ( Shirley Basin, Wyoming ) shutting down in 1992. 34. The mine began operation in 1966, as an open pit mine and eventually evolved into an underground mine. 35. But police failed to hold back crowds flocking to the open pit mine in support of the strikers. 36. Jwaneng is an open pit mine . 37. In 1858, African-American miners working in open pit mines were the first to discover dinosaur fossils in Maryland. 38. San Francisco-based Homestake said it will continue processing ore from the complex's open pit mine during the shutdown. 39. In 2012, protests against the Conga open pit mine became widespread, and in July five protesters were killed. 40. Construction of an open pit mine began in May 1970 and in mid-1973 the mine was declared fully operational.
