Lucky Friday is a polymetallic underground mine located in the Coeur D'Alene region of Idaho that has been in operation since 1941. The #4 shaft is expected to extend mine life to at least 2039. Board approval for the go ahead of the project was given in 2011. The final capital cost of the project is US$225 million of which approximately US$205 million was already spent as of December 31 2015. The shaft reached its final depth in May 2016 and was operational by the end of the year.