Chollar Mine. First located in 1859, the Chollar was consolidated with the Potosi in 1865. As the Chollar-Potosi, it was one of the leading producers on the Comstock. The Nevada mill was erected here in 1887 to process low-grade Chollar ore. It was the last to use the Washoe pan process, but the first on the Comstock to generate and utilize electric power.