John and Mary Marks use a grinding wheel to sharpen tools at the Oro Grande survey and engineering crew's campsite. Mary is wearing leather gloves, a dark bodice with puffed sleeves tucked into a long, light-colored striped skirt, and a wide-brimmed hat. Standing, John is dressed in a waistcoat over a long-sleeved shirt, with dark pants and leather boots. There is an anvil and pickaxes behind them. The surrounding landscape includes evergreen trees and sage bushes, with a view of mountains in the background.