What Is Your Grade?
March 2021 by Thom Seal, PhD, PE
After paying for the mine fleet, mill capital, supplies, fuel, power and labor, at today’s metal prices, does this mine make a profit?
The first step in my recovery process after milling the ore to the desired size is to table it. On this particular ore, I get good results milling it to minus 100 mesh.
I had never run an impact mill before, but anything involving rocks, water and a big electric motor sounded great.
Ore testing and other advice for starting up a mining operation.
I have figured out over the years that the winning combination is hard work, persistence, knowledge, and a little luck. This leads me to describe one of my best finds ever, a “honey hole” of placer gold, if you will.
Through the milling process, the rock must be crushed and the values extracted. Let’s break down our discussion into the different parts and elements of the mill…
Starting small with quick profitability gives you a lot of financial elbow room plus real-world experience that can be used for final mill design.
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