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Small Scale Hardrock (Lode) Mining


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I have been hardrock mining most of my life. I must say it is a hard way to make a living but the rewards can be good at times.

It has taken years of learning and a lot of prying the tricks of the trade out of the oldtimers to become successful at it. It is also very expensive. The last time I worked the mine it was costing 1200.00 a foot in a 5x7 foot drift. That is including track,ties,waterline, airline,powder,fuse,caps,drill steel and fuel. I never estimated the milling cost.

One of the biggest problems now days is putting up the money to get powder.

The government wants you to get separate permits for each component you use in blasting. You must also have a certified powder box and they are pricey. On top of that you must also have the powder delivered by the powder company. The last time the delivery fee was $1000.00.

I'm not trying to discourage anybody from doing it. There are areas that have the right geology that can be mined with less cost. I worked a mine years ago that was in some very soft ground. I was able to take out the ore shoot with electric jack hammers,but I did have the cost of timbering it.

It is one heck of alot of fun when you are on the gold. But very expensive and stressful when you are not!

Root

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Feel like sharing any of the old tricks of the trade that had to be pried from the oldtimers?  :D

 

I'm also curious about your prospecting methods. Is it basically just going from exposure to exposure, looking for free gold, grabbing samples to take home and crush or assay? Do you use something like a Gold Bug 2? Any helpful prospecting tips? Were your mines re-entries of old discoveries or brand new discoveries that you made?

 

My interests are basically finding a good surface vein and working it open pit style with a jackhammer like in the ICMJ article or maybe an excavator or small dozer, or I guess however the vein determines I need to excavate it, until it gets to the point where I have to do a lot of underground work, and then to sell it once it's proven up.

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The tricks of the trade are usually only Givin to those that have put in the time.
I could write all day on them.
One of the best books I have seen on the subject,that have most of them in it,is a book by Koehler S. Stout "The Profitable Small Mine" you will find what you need in this book. You can find it on Amazon.

I have mined in old workings mostly,but I have been lucky enough to find a few of my own that the oldtimers missed. Mostly I work mines that throw pockets. Once the frist pocket is found it is only a matter of staying on the shoot line to find more.
It is also usually a smaller vein that makes them. They are easier to work with a one or two man operation and the out lay is small and profit is higher.The milling costs are small too. Most of the gold is found in bunches of high grade rock,so milling is usually only done with a few ton that has surrounded the pocket.

One of the best pieces of advise I can give is to do your research on the area that you are interested in. Try to find out what made the ore shoots in your area.
You must learn how to read the ground. In most places there is a geologic structure that causes the gold to occur in rich enough quality to make a profit. These are at the contacts of a dike and quartz with a third leg that is usually a small seam of iron or calcium or???
If you ask me assays are a waste of time unless you can do hundreds of them. I crush the rock I'm interested in and pan it. I have done it enough that I can give a good estimate of what it runs in free gold. As for the sulfide or telluride ore it must be sent off for assay.

I have used detectors under ground in the search for gold and I have had success in doing it,but I think the pan is a better tool for this type of prospecting.

Root

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I appreciate the tips, especially about the book.  I've got some property with a filled in mine near Placerville that I need to determine if it is worth working.  I've done the research, and can't find anything on it in county records, so I'm pretty much stuck excavating and prospecting it myself (with the help of my son-in-law).  It's been a project for vacations, but in a few months when I retire I'm going to get serious about it.

 

I do have two quick questions that I hope you will answer.  Do you do your own milling, or do you send the ore out?  The second question is related - do you only use gravity separation for extracting the gold, and do you do that yourself?  Ah, I guess that was three questions.

 

JT

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I'll check that book out too, thanks.

 

When you are working pockety country have you ever found veins that only have 1 pocket and then nothing else? How far will you go with lowgrade or nothing before you call it quits on that vein?

 

I'm curious because I've found pockets, but they are always just "1 and done". But I've never gone more than 3-4ft beyond the initial pocket. The quartz around the pockets has been almost barren and went from brecciated/vuggy to solid so I just gave up. Is it worth it to keep going further on those ones?

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Mud Men: Pocket Miners of Southwest Oregon—Part I by Tom Bohmker (free)
 
More ICMJ Articles by Tom Bohmker (subscription required)
 
George Duffy Jr.—Pocket Miner Extraordinaire by Jim Straight (subscription required)
 
And just found this, new in 2015, a bit on the heavy side but good tidbits and the price is right
 
AN INTRODUCTION TO GEOLOGY AND HARD ROCK MINING 2015
By Dr. Willard Lacy

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Jim I mill my own rock. I do use gravity for the getting the concentrates. Or the best thing I have found are Knudson bowls they seem to get a high percentage of the heavy stuff.

Jasong It is hard to answer your questions about pockets without seeing the structure that you are working on. You must always try to figure out why the gold is pocketing in that area. There will be a indacator. Once that is determined it is easier to follow the shoot. It may be nothing more than a crack in the rock or a rusty seam but it will prospect. You may only get one color per pan but you have to follow it to the next pocket. I have all ways found more than one pocket usually the further apart they are the bigger they have been. Almost all of them have been within 12 feet of the last one. The more gold pockets you find the more you will learn about what makes them forum in the area you are working. It will make it easier to find the next one. I'm assuming the vuggy pocket you found was close to the surface. If this is the case the other minerals leached out and left the gold behind but this is only a assumption.With out seeing it I'm only guessing.

When most pockets are found there is usually a lot of mud in with them this is the other minerals that formed with the gold.

I have not mined far from where I grew up and live so I can only give you advice on my experience from within a small mining district. Every district seems to have its own set of rules as to why the gold forums the way that it does and sometimes the individual mines within a district will not follow these rules. When you find gold in a pocket learn all you can about why it is there.

If it were easy everybody would be doing it.

Reseach is 90% of becoming successfull at mining in a new area.Finding the clues within the reports from the past can be just as fun as finding that first pocket.

Root

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It can be easier to find the ore shoots if the veins and country rock are exposed.

Look for areas of contact. There can be a ton of different ways this can occur.

What I try to find is where you have a contact of two types of country rock. Lets say greenstone and slate. Sometimes the slate will be on one side of the vein and greenstone on the other but I like it better if they are running up aginst the vein both from the same side and the quartz vain has cut them or has ran into one and turned a bit.Even better is to have a dike hitting the quartz vain in or near this contact. Usually there will be a solution seam that has brought the gold into this ore shoot.It may be nothing more than a crack usually full of mud or iron. It will be coming out of the county rock or runing with a dike. Where it stays with the quartz will be the shoot. Sometimes it can cross it quickly and the shoot will be smaller than if it runs on more of a angle like close to the strike of the vein. There are just so many different ways ore shoots can forum but what most have in common is they are at contacts. The more contacts the better the chance for a ore shoot.

Also think of a quartz vein as a stream if it turns,widens or gets narrow the gold falls out of solution and gets deposited just like in a stream. Gold does not all ways deposit in these contacts or changes. It is just the best places to look first.

Root

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