It was underground, hard-rock mining operations that transformed California gold mining into a corporate activity. It was in the Northern Mines, clustered around Grass Valley, which dominated underground mining. In the beginning, the gold-bearing quartz was wrenched from underground veins by backbreaking, dimly lit sweat and blood. However, imported miners from Cornwall and Wales adapted ancient European mining techniques and brought modern technology to the enterprise. The miners followed the veins and blasted the gold from the quartz. The mineshafts and drifts were then “mucked out” and the gold-bearing ore was transported to the surface for processing.
Sluice boxes were extended versions of the Long Tom. A number of sluice boxes were frequently connected into a long line, and large crews of miners were utilized. Ground sluicing was a variant of this practice. Rivers would be diverted into ditches and would soften the gold-bearing dirt and rock. The miners would loosen the dirt and rocks with picks and allow water and gravity to transport the material down to a sluice box. As with the Long Tom, gold was finally removed from the sluice boxes by panning.
Panning was the oldest and simplest way to separate gold from surrounding rock. It was the most basic method to obtain placer gold. The basic procedure was to place some gold-bearing materials, such as river gravel, into a shallow pan, add some water, and then carefully swirl the mixture around so the water and light material spilled over the side. If all went well, the heavier gold nuggets or gold dust would settle to the bottom of the pan.