Ophir - The much sought-after site of King Solomon's mines. Two poor Irish prospectors gave the name to a claim near Carson City, Nevada, in Washoe County, which soon thereafter became known as the fabulous Comstock Lode. There is also Mt. Ophir on Highway 49 between Mt. Bullion and Bear Valley in Mariposa County, where the remains of an early private mint can be seen among several interesting rock foundations.
Ore - Rock containing enough precious metal to make it worth mining.
Overburden - Material, like dirt and rock, covering the gold-bearing veins or gravel that was removed by hydraulicking.
Panning - A simple but slow method of mining. Gravels from the stream bed are washed in a pan, causing lighter materials to spill over the side and heavier gold-bearing particles to settle to the bottom.
Pay Dirt - Expression describing gold-rich ore, sand, or gravel taken from claims. The claim became "pay dirt" when the miner realized a profit after his expenses had been covered.
Pelton Wheel - A huge waterwheel that produced power for hardrock mining equipment, invented by Lester Pelton in 1878. Examples have been preserved at North Star Mining Museum in Grass Valley and at Sierra County Historical Park & Museum near Sierra City.
Physics - The science dealing with the properties, changes, interaction, etc., of energy and matter, developed from alchemy in the Middle Ages.
Placer - A deposit of gravel or sand containing particles of gold that can be washed out. Usually eroded from the hills or deposited by a river.
Placer Mining - Mining on the surface. A process of extracting surface gold from ore-bearing gravels by panning, dredging, and sluicing. This was the method used by California's first prospectors. Because water was essential to the process, most placer claims were located along creeks, streams, and rivers. At dry diggings (there were at least 50 of them in the Mother Lode), the water was brought in via flumes and ravines. Contrasted with placer mining is hardrock (quartz) mining and hydraulic mining.
Pocket - A small but rich concentration of gold in a quartz vein, or gold-bearing gravel in a hole or low spot in a stream bed.
Poke - (1) A small sack or bag, usually a crude leather pouch, in which a miner carried his gold dust and nuggets. A pinch from his poke could by him a shot of whiskey. (2) Also, his "poke" could be the amount of gold he owned.
Prospector - A miner searching gold-finding possibilities by examining a panful of placers to see if the area will yield enough profit to pay his day's expenses. (See Pay Dirt)
Quartz - A common, hard mineral, often with brilliant crystals, generally found in large masses or veins. The quartz in the Sierra Nevada was mined for its gold content.
Quartz Mining - See Hardrock Mining
Quicksilver - Mercury (Hg.): a heavy, silver-white metallic chemical element, l iquid at ordinary temperatures. Used to help capture gold particles in sluicing when placed at the riffles or ribs in the box.
Retort - A high-temperature furnace used in refining gold. Amalgam is super-heated so the mercury is vaporized and saved, and the gold is formed into bars.
Riffles - The wooden ribs or slats placed on the bottom of rockers, long toms and sluice boxes to capture the heavy gold particles while the lighter material was washed away. Sometimes mercury was placed at the riffles to help collect the gold on its way through the box.
Rocker (Cradle) - Rectangular wooden box set on rockers, used in mining. The rocking motion caused the mixture of dirt and water to flow through the box, with gold-bearing particles trapped by riffles on the bottom. It was also called a cradle because of its resemblance. Improved upon by the long tom and the sluice box.
Slickins - The debris, mud, and silt that washed down the river from hydraulic mining. It plugged important water ways, covered valuable farmland with thick gunge, and even damaged San Francisco Bay.
Sluice Box - A modified rocker. Water power forced dirt through the box, a sloping trough or inclined flume, and heavy gold-bearing particles were caught by riffles or slats. Mercury (quicksilver) was sometimes placed behind the riffles to catch the gold. Hydraulic mining used a long series of sluices.
Sniping - Reworking an abandoned claim, practiced by the Chinese miners, who often found more gold than the original miners.
Stamp Mill - A mill built to break up and grind gold-bearing ore, saving the gold by amalgamation. A mill could have any number of "stamps".
Stamps - Metal arms at a stamp mlll that raised and lowered like battering rams to crush the ore so the gold could be extracted.
Strike - A newly-found concentration of gold (or silver) rich enough to be mined profitably.
Sulphurets (Sulfurets) - Gold in its uneroded state, alloyed with iron, and combined with sulfur as iron pyrite, making it unrefineable. The gold will not release from the sulfides and counteracts the effect of the mercury during the refining process.