Ask The Experts

Ask the Experts - Old workings & tailings: What are my options?

February 2012 by Chris

Q: I am looking to do some gold mining in California. It’s a 2,000-acre property that was mined 100 years ago, still has the old workings, tailings, etc. I am looking to recover gold from the old waste/tailings... plus possibly strip mine some of it. What are my options?? This would be a small operation.

Leon Styles
via email

A: Well, the first step would be to get a better handle on just what you have. The tailings, be they mine or mill tailings, should be sampled by someone who knows how to do this, using a backhoe to cut trenches so that the samples don’t just reflect what is on the surface. The outcropping ore materials exposed on the surface should be sampled as well. Though you may be surface mining, you probably won’t be strip mining, as that’s a technique utilized for mining coal.

Once you know the amount of gold in the tailings and near surface ores, you can run tests to see if gravity methods or leaching will offer the best recovery. There are lots of options—too many to name and describe—but the first step is to get a good idea of exactly what you have. A small treatment operation capable of processing one ton of rock an hour will cost $15,000 to $20,000 to set up at a minimum, as low cost and hard rock mining just don’t go together. So, before you invest money in equipment, invest in sampling your property.