Pioneer Ore Sampling Company
Built in 1874, this mill was the largest and longest one in operation. Extracted ore from the mines was run through a series of rollers and crushers and assayed for metal content before being taken by rail to ports on the west coast. Once loaded onto barges, this ore was shipped to northeast Europe. Because the ore was of such a high grade it was very profitable, earning more than one hundred dollars per ton. The mill was constructed from wood with sheet metal sides. An early feature was electric lighting. Heat for the facility was provided by coal.
In 1887, the mill was destroyed by fire and rebuilt within a month. Every year, the Pioneer Sampling Mill was cleaned out and decorated for one of the social highlights of the year: The Annual Masked Ball. During the day, Richard Macintosh ran the plant until Arthur Cushing arrived to take over on the night shift. James Smith was the engineer and William D. Kuhre was the bookkeeper. Sharing a fate similar to the other Sandy sampling mills, the mill was closed in 1907. In 1914, it was finally torn down and the lumber sold.