Miners Clean Washington Rivers and Streams
May 2007 by Richard HolcombThe Washington Department of Health has issued several warnings about mercury contamination in fish and shellfish. The small-scale mining community is the only group that is actively removing mercury and lead from the waterways of the State of Washington using the only economically feasible method available—with suction dredges and other small-scale mining equipment.
...was all this about grazing fees and the desert tortoise, or something more?
How do I set up a small placer operation?
I had never run an impact mill before, but anything involving rocks, water and a big electric motor sounded great.
At the Gold Quarry open-pit mine, a massive electric shovel scoops 40 tons of earth in a single bite and dumps it into a 325,000-pound truck the size of a two-story house.
Using a porcelain evaporating dish, place concentrates or head ore, equal to a tablespoon, in 60cc of aqua regia. Boil almost to dry, then add 10cc HCl (hydrochloric or muratic acid) and heat for a few minutes, and then add 30cc of water and bring to boil. Let cool while the solids are being allowed to settle. Using a pipette...
Swedes were the first to note variations in the Earth's magnetic field, circa 1640, and they were the first to use the dip needle. They made the first magnetometer in 1870.
The first Madero Revolution broke out in Mexico on November 20, 1910. On December 27, a revolutionary party exacted supplies, arms, and mules from the company until January 7, 1911, when the 7th Cavalry Regiment of the federal government destroyed three and a half tons of their dynamite near Baquiachi. On September 8, 1912, Batopilas was captured, a local garrison driven out, and the company forced to pay 10,000 pesos. Federal forces retook the town September 19.
The Bawl Mill • Ask the Experts—Where can I find plans for a home-built suction dredge? • Ask The Experts—Can you help explain the ratings in Melman On Gold & Silver? • Recovering Values from Black Sands • Typhoon Exploration—Junior Mining Company Moves Forward in Quebec • Kalgoorlie, Australia—Born of Gold • Colorado Court Rules on Cyanide Ban • Selling Your Gold—Where To Start • The Business of Mines—Consider Your Tax Deductions Now • Exploration, Development and Taxes • US v. Donald Eno—IBLA Rules in Favor of Miner • Melman on Gold & Silver • Mining Stock Quotes, Mineral & Metal Prices • Looking Back