Hard Rock 101: Mechanical Techniques
June 2020 by John Norman
Since we know that the secret to breaking rock is applying force from the inside out (putting tension on the rock), we will be looking at ways we can generate force using human and machine power.
Imagine you have located a source of virgin placer ore containing immense gold value. Now imagine that there is a 10-ton monolith of extremely hard gneiss in between you and payday.
Centrifugal bowls are very efficient, and with proper operation they can consistently achieve gold recoveries above 95% with gold of about 50 mesh size.
Any good books on mineralized faults and contacts?
...most prospectors don't even think about the conductivity of minerals, but there are some that do conduct electricity to a certain degree, so metal detectors will respond to them.
It was time to prime the pump and start the engine! Dan’s priming method is to use a small, submersible, 12-volt pump. My priming method is to use a hand-operated diaphragm pump.
Most prospectors understand placer mining a lot better than hard rock mining and don’t realize the amount of work that goes into processing different types of hard rock ore.
Our group of independent miners have been busy crafting a uniquely designed ladder/ore cart track from the bottom of an 85-foot mine shaft in a historical hard rock mine.
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