June 14, 2010

An Introduction To Prospecting

by Jim Zambenini


This is an overview of how to get started in prospecting. I will cover the very basics as thoroughly as I can without making a book. I have included a brief discussion on sluicing and using power equipment. This document is an experiment and your feedback would be appreciated (hey, we don’t even have a counter, let alone fancy usage analysis). The best place to start educating yourself about prospecting is the local library. You may be amazed at how many books you can find about searching for gold and how to use a pan. Many Internet sites on recreational prospecting contain good basic information you can use for references. While recreational prospecting can include deserts, mountainsides, and flatlands, this page will only address prospecting around gold bearing streams and rivers.

While some do strike it rich, if that is your goal at the outset, I can almost guarantee your disappointment. What you will gain are great experiences, good friendships, a new understanding of the great outdoors, and some nice gold to show your family and friends. If you do decide to become a recreational prospector, then we encourage you to approach prospecting as a responsible member of the mining community. Please read the page entitled “Keeping Your Prospecting Rights”.

Where To Go
The best place to start looking for gold is in an area where gold has been found before. Nobody gets it all! The California Gold Rush removed only a small percentage of the gold which actually exists in the Mother Lode. People are frequently discovering new gold bearing areas. Yes you should look in your own back yard, I just suggest you wait until you’ve had some positive experience in sampling and finding gold.

In California, there are several areas open to the public for recreational prospecting, including the Auburn State Recreation Area and the South Yuba Recreation Lands. BLM land and National Forest land are open to prospecting with some exceptions including patented land and valid mining claims.

What To Look For
The tired but true cliche is that “gold is where you find it”. By knowing how gold forms and is moved and concentrated by nature into placer deposits you can get some good ideas about where it will he. However, frequently it will not be there and frequently you will find it where it shouldn’t be. This is maybe the best advice anyone can give you is SAMPLE, SAMPLE, SAMPLE! Having the best equipment and working it ten hours a day won’t help you get gold if you are digging somewhere where there’s little or no gold. You should sample high and low and keep moving along until you find a spot that’s got some nice “color”, then keep sampling along for a bit until you’re convinced that you’re not getting into something better, then go back and go to work! I suggest your first few trips be panning only. The time to set up a sluice or power equipment is when you feel you have a spot or two that produce consistent satisfactory results.

As you educate yourself about prospecting you will learn that gold tends to deposit where the stream flow slows (i.e., the inside of bends, a widening part of the stream following faster water, a marked decrease in stream bed slope, and downstream of large obstructions like boulders, trees, and humps in the bedrock). Also you will learn that nuggets and larger flakes are mostly found on bedrock (which prevented it from settling deeper) while fine gold and small flakes can deposit in stratified streaks at various levels. These are the best places to start sampling. You should throw or scrape off the upper cobbles and gravel and sample the sand and gravel closest to bedrock. More importantly you should look for cracks and crevices in the bedrock, break them open and clean them out. You should sample spots from the water’s edge up to the high water mark of the stream. You can sample spots underwater but keep your shovel level as you lift.

Equipment To Take
You should pack light for a sampling trip because you want to cover the most ground you can reasonably sample. These are the bare essential tools for your task:

  • A good gold pan (details in the panning section below).
  • A regulation shovel (with point, not flat bladed) for removing the top layers of cobble and gravel and digging sample holes.
  • A good sturdy hand shovel for digging in smaller spaces (like a garden trowel).
  • A good hand pick for breaking open crevices and loosening compacted gravel (trust me;buy an Estwing).
  • An old tablespoon and an old teaspoon for scooping material out of bedrock crevices.
  • A couple good crevice tools for cleaning out tighter crevices. You can make these by bending the end of a long screwdriver 90 degrees but the tools made for this purpose are far superior. I suggest a long flat-bar claw and a shorter rod-stock tool with a scoop end and a pick end.
  • A small plastic vial for your “pickers”.
  • A wide-mouthed plastic jug to save your black sand and fine gold.
  • Knee pads, don’t leave home without ’em!

Additional optional tools:

  • An Estwing “Gad pry-bar”. This is an invaluable companion to your hand pick.
  • Tweezers, snuffer bottle, plastic eyedropper for recovering gold from your pan.
  • A suction bulb. This is my favorite tool. Similar to a turkey baster, with the suction tube extending half way into the bulb. This enables you to suck up the gold and black sand out of your pan quickly and move on. This tool is a necessity for sniping (more on this later). Note: You must set the tube to be 1/2 to 3/4 of the way into the bulb and then epoxy the tube to the ferrule so the tube can’t slide in and out (you’ll see what I mean when your holding one).
  • A large block sponge for dewatering holes and crevices so you can accurately scoop out the material.
Basic Prospecting Gear

With the exception of the shovel and pan, all of this will fit in a day pack or a five-gallon bucket so you can sample half a dozen pans around a spot and then pick up and move along.

How To Pan
PANNING IS PARAMOUNT! If you want to have fun and be successful at this then you must be comfortable and proficient with a pan. There are only three ways to find placer gold without using a pan: metal detecting, sniping (more on this later), and tripping over huge nuggets (very rare). In many instances, metal detecting and sniping require the use of a pan also. Sluicing, dredging, highbanking, dry vacuuming, and dry washing all require the use of a pan for the final recovery of gold. If you’re not proficient with a pan then you will be throwing away the gold that your equipment so carefully concentrated for you!

NOTE: Any time you are panning “concentrates” from a sluice, dredge, etc., you should pan into a safety pan or tub so you can re-pan the material several times.

I cannot adequately cover detailed panning instructions here but I’ll give you the basics. Get some books on how to pan and watch others pan when you’re out in the field. Everyone pans differently and you will develop your own style as you get more proficient. There are a wide variety of pans available and, while you can do this with a pie plate or a Frisbee, a good pan is necessary for speed and accuracy. I recommend a plastic pan with riffles (like little stairs built into the side) and a drop bottom (so there is a small lip where the sides meet the bottom). Specifically, I recommend you buy a Garret Gravity Trap pan from your local prospecting supply house. Practice at home, preferably in a local creek, using cut up and shaved fishing sinkers as small nuggets and flakes. Find a fairly calm spot on the bank, don’t pan in fast water. Lead is much lighter than gold, so if you’re getting all the test nuggets and flakes then you’ll get the gold. Once proficient, it should not take you more than 3-4 minutes to run a full sample pan down to black sand and gold. Don’t get sloppy but the faster that you can accurately pan, the more samples you can pan, and thus the more gold you can find.

Panning is a four-step process with the middle two steps repeating until you’re ready for the fourth step. Step One is to submerge the pan of material and work the material with your hands until it’s thoroughly wetted and mixed. Step Two is to stratify the material by using a fairly vigorous, small circular motion while keeping the pan level and the material below the water surface. When stratifying, your motion should not be so vigorous as to lose material out of the pan. Because gold is so much heavier than any other material in the pan, even the smallest pieces sink to the bottom readily during the stratification process. You are not in danger of losing the gold during this process. The risk occurs when you are washing (step 3), thus the need to frequently repeat stratifying. In Step Three you tilt the pan slightly away from you and use a more gentle circular motion to wash the top layer of sand and gravel over the lip and out of the pan. During the washing action the material should be below the water’s surface AT ALL TIMES ( don’t use a lifting and pouring action). When you feel you’ve washed about an inch of surface material out of the pan, level the pan again and restratify as in Step Two. As you repeat Steps Two and Three, slightly increase the tilt of the pan as the volume of material decreases. If your pan has riffles, at the point when you have about a cup or two of material left in the pan then the riffles will begin to inhibit the washing action and you should rotate the pan to use the side without riffles. Keep alternately stratifying and washing until there is almost nothing left in the pan except black sand – generally about two tablespoons. Step Four is separating the gold in the pan from the black sand (clearly we hope you have both). There is a variety of ways to accomplish such a difficult task. With the concentrates gathered along one edge of the pan bottom, and having that edge away from you, tilt your side of the pan very slightly down, gently swirl the water around while gently tapping the high side. This should wash the black sand down towards you across the bottom of the pan while keeping the heavier gold at the top (or away) side. The gold that’s not “pickers” can be sucked up with an eyedropper or snuffer bottle. I strongly recommend that you not waste time in the field separating gold from black sand; instead, give the pan a back swirl to see how much gold you’re getting and to pick out anything of size. Wash the concentrates into a plastic jug for home panning enjoyment.

How To Snipe
Sniping (pronounced snyping) is a term that dates back to at least the depression-era when transient people who made their beans by mining were referred to as snipers. I have heard it, and seen it in print, referring to a variety of mining activities. In modern recreational mining circles it is a term used to describe working underwater by hand with a mask and snorkle.

This type of mining is great fun, but it’s not for everyone. There is an inherent danger in swimming most mountain streams. The force of a river is awesome and should always be treated with respect and caution. If you are not a strong swimmer and in good health, then don’t risk it.

When sniping, you are not looking for fine gold but for nuggets and flakes that are trapped in the cracks and crevices of bedrock. You simply fan the gravel off of the bedrock with your hand and arm to expose the creyices in the bedrock. You then break the crevices open and loosen the material with your rock pick. Next, fan the crevice with your hand, creating currents which blow the sand and gravel out of the crevice and expose the gold underneath. A suction bulb is the best tool for extracting the exposed pieces of gold (see above in prospecting tools); I made a surgical tubing handle for mine so it’s always on my wrist ( the river wants to take your bulb!). You will be surprised at the amount of force you can use to clear out the sand and gravel without loosing gold. Lighten up a little as you approach the bottom of the crevice and you may get a few extra small flakes. Work crevices to the bottom and then break up the bottom and re-fan it. It’s hard to get a feel for this at first (since it’s rare to jump in and find gold immediately) but you will start to get nails, fishing sinkers, and bullets which are much lighter than gold and can use them to gauge your force. Please remove this stuff and pack it out with you. You should look for crevices with tightly packed gravel in them since this is an indication that they have not recently been worked.

Sniping on the American River

The great thing about sniping {besides being one with the river and watching the fish) is your ability to move along. Try a few crevices and move on if you’re not hitting anything. You can work only as deep as you can reach, so you need to cover ground. Don’t take in more tools than you can carry in your two hands.

Most creeks and rivers run pretty cold most of the year and I suggest you wear a good thick Farmer John’s style wet suit. Use cut pieces of car inner tubes to protect your suit from the thigh to the shin. Wear some good knee pads over these. If you can find a motorcycle tube, make some elbow pads. Don’t use diving booties for kicking around on sharp bedrock. Instead, get neoprene socks and buy the cheapest K-Mart work boots you can find (look for boots that are “all man made materials” as they hold up underwater much better than leather). The style of mask and snorkel is a personal preference but I recommend a mask with a purge valve because it’s hard to use conventional clearing techniques in swift currents. Snorkels are designed for looking ahead, but when you’re sniping, you look down. For this reason I cut my snorkels and add a six inch PVC extension. WARNING: If you add too much extension then you will be breathing your previous exhalation and not getting fresh air! This is another good reason for a mask with a purge valve, inhale through your mouth (snorkel) and exhale through your nose (mask).

Basic Sniping Gear

Mining can be frustrating with days of getting “skunked”. Sampling can be especially difficult when you’re not finding much and you’re tempted to go back to that one spot where you were getting a little color. Remember two things:

  1. Every spot where you find little or nothing is valuable, not wasted time. This is how you find decent deposits and prevent yourself from going to an unproductive area time after time.
  2. Recreational prospecting is recreational. The gold you find is just the icing on the cake. The real payoff is the gorgeous scenery, the friends you’ll make, the education and experiences you’ll gain, and good healthy workouts (the more gold and trash you pack out, the more calories you burn!).

If you’re new at this, don’t be shy about approaching miners. The majority of us are extremely friendly and helpful. Most of us enjoy sharing our knowledge and experience, since we vividly remember trying to learn how to work that darn pan.

The Next Step
Okay, so you like prospecting and you’ve found a little gold. Now you want to take the next step. Buy or build a sluice box. The bottom line is that, when you are in a productive area, the more material you process, the more gold you recover. A sluice box will enable you to run five to ten times the material you can pan in a day. Best of all, it’s easy to pack in. Just like your pan, a sluice box stratifies the material allowing the gold to settle out. The gold is then trapped in low pressure zones on the downstream side of the riffles (just as gold deposits downstream of obstacles in a river). I recommend you spend the sixty to seventy bucks to buy a sluice at your friendly prospecting supply house. The sluice you get will be light, durable, have the right riffle angles, the right carpet or miners moss, and it will be easy to break down and clean out. If you use a course classifier screen that fits on a five gallon bucket then you won’t be wasting time carrying and sluicing rock that’s more than one inch diameter.

Power Equipment
There is a time and a place for everything but don’t jump into power equipment without a good reason. When you’re out sampling and panning think about the reality of packing heavy motors and making the necessary multiple trips into an area. Do the conditions justify the labor and expense? For example, if you’re at a wide calm spot of a stream where you can’t run a sluice box then maybe you do need a highbanker. On the other hand, most of the gold you can reach with a small dredge (that doesn’t have breathing air) you can get by sniping, maybe more, since you can cover more ground. When it comes to dredging, I recommend nothing smaller than a four-inch diameter nozzle with a breathing air compressor . WARNING: This kind of dredging can be fatal if you do not take the time to do everything safely. You should research all aspects of dredging safety including making safe holes, preventing CO poisoning from your exhaust, and safely moving boulders. There is no accurate way to sample an area for dredging without using a dredge to punch sample holes (good sniping along the banks is no guarantee). To get this involved, and do it right, you need to plan carefully. You need enough time to pack your gear in and out, to sample, and to work.

Power equipment mining can be fun and profitable but it is very different from panning and sluicing. Know what you’re getting into.