Let us help you recover valuable metals. 888-437-1187


History & Geology

Know Your District

After driving for hours with an uncontainable excitement about what you might find in a new gold district, you step out of the car and look out on what seems like an endless horizon. Once you are on the ground, where exactly do you start your search for that elusive yellow metal? Unfortunately, gold doesn’t always follow the rules and what you’ve found to be true in other districts might not apply here. Some common traits among successful prospectors are quality research, knowing what signs to look for, and an ability to always be learning out in the field.

Before you ever take a trip into the gold fields you’ve hopefully started out by doing research on the area you want to prospect. This can save you from much fruitless effort. For instance, if you are a metal detectorist, you would want to be sure your area is a producer of coarse, nuggety gold. There are many fabulously rich gold districts that have only produced fine gold, with nuggets being extremely rare. If you set out detecting in one of these districts you can find yourself trying to squeeze blood out of a turnip. On the other hand, you might have great success there if you’re using a sluice box or a drywasher.

Some of the best sources of information are old government reports and bulletins that were issued by state mineralogists, the USGS and the now defunct US Bureau of Mines. Since these documents have no copyright protection, you can find Vast goldfieldsmany of them on the Internet. These reports and bulletins contain information on many gold districts, often including what the old timers were finding, the types of rocks present and specific locations where gold and other precious metals were found. You can combine this with information contained in more recent books and magazines to give yourself leads in a particular district.

Don’t ignore geologic maps in your research. If you can find geologic maps on an area of interest you may be able to locate a commonality between where mines and workings are located and where certain geologic features are found. It can be quite obvious when looking at hard rock mines sometimes. You may see that at certain contact points between features there will be mines situated all along it. With old tertiary channels in California’s Motherlode, andesite capped these old rivers. Those rich river gravels were often worked by drift mining under the andesite cap. You may see a couple of these drift mines at the edge of the caps and could reasonably presume that river gravels bled out from under the cap to enrich the drainages around where those drift mines show up on the maps. With this research you’ve not only learned which districts would be suited to your needs, you’ve also begun to learn about some of the specific items you should be looking for in the district.

While gold is usually associated with things such as schist, greenstones and quartz, these are by no means the exclusive indicators of gold. If you were looking for these signs in some of the districts where I’ve had my best success you would never be successful. Even in districts of seemingly typical gold geology, you will find areas that will produce better gold than others. This is where the ability to continually learn from your experiences will help fill your poke.

I have found no better source for learning a new area than those who have found gold there before me. And while many prospectors can be quite tight lipped about what they’ve learned or where they’ve found gold, those who have passed on readily give up their knowledge if you’re willing to look and learn. We have to remember that the earliest miners were not geologists, but came from a variety of backgrounds. Their survival depended on finding enough gold so they worked hard and adapted to whatever challenges these new areas presented. Through their trial and error, persistence and extremely hard work they left clues we should be looking for.

“Why did they look here?” is one of the first things many new prospectors say when they see old workings. In your eyes that spot may look the same as all the surrounding area. When you find these old workings look for which rocks and minerals are present. Take notice of everything from the terrain to the material they were working. Make a note of similarities with other nearby workings. Does this one have the same rocks present as the last one and are they not found in most places in the area? If you’ve noticed a similarity you may have just found a good indicator.

One district where I have had great success has little or no schist, is primarily granitic, and has an abundance of quartz. While this basic geology covers many square miles—most of it barren—there are unique indicators I have found that cause me to immediately fire up my detector. In observing where the old timers worked I noticed that magnetite was always present in the old placer workings. The many gullies in the area are void of magnetite and the old miners avoided them. As a result, I work areas where I find magnetite, whether the old timers worked them or not, and this method has produced many quality nuggets.

In this same district, my brother and prospecting partner Mark made these same observations and used these facts with great success in detecting gold. In one location he recovered many good gold-quartz specimens based on previous observations of old prospects and pocket locations. It was right where a vein of magnetite intersected a quartz vein.

The old timers likely didn’t know the gold dropped out of solution at this spot but they definitely picked up on the fact that gold was associated with magnetite. My point is: You don’t have to be an expert in geology to have success, but your success will come more often with observations like these.

At another location, I found the geology looked very different from any place I had ever searched but there were a number of what appeared to be pocket mines in the area. The one thing I had observed was that at every hole the old timers dug there appeared to have calcite in small amounts. This led me to search an area where I quickly pulled out several half-ounce nuggets with a unique character to them—attached to all of them were small amounts of calcite. Later, not but a few feet away, a specimen in calcite was found that contained seven ounces of gold.

It can be daunting finding that first piece of gold in a new area. In this modern day of technology and information, you can help your cause greatly by availing yourself of all the research available. However, when you step foot into the vastness of the gold fields your best tool can be the same tool used since man’s beginning—the ability to discern information from observations. This tool helped the old timers keep food in their bellies and find gobs of gold. Much gold is still out there awaiting discovery. If you can research these old locations, make observations and learn from the old timers past work, you can find your share of the gold, too.
© ICMJ's Prospecting and Mining Journal, CMJ Inc.
Next Article »« Previous Article

Add a Comment

Additional articles that might interest you...

The Coolgardie Gold Mining Camp of Southern California

The area was mined intermittently from around 1900 to 1915, but was also mined in the late 1800s, with a total output valued at about $100,000, which is around $9.5 million at the current gold price.

The Seven Troughs Mining District

The favorable geology of the northeastern and central parts of the Seven Troughs Range are the parts most interesting to prospectors. They are underlain by a thick sequence of Tertiary volcanic rocks, mostly rhyolites and andesites.

Prospecting for Diamonds

Let’s take a look at diamonds and diamond mining and see how they form, how they are used beyond just jewelry, and what leads geologists to find diamond deposits.

Prospecting for Copper—What to Look for on the Outcrop

For the prospector, knowing what oxidized hydrothermal alteration looks like in the field is an important exploration tool.

How to Recognize Hard Rock Gold Ores

I regularly get inquiries along the line of: “Hey, I found this rock, and I think it might be gold ore. How can I tell?” Prospectors are always on the lookout for gold-bearing rocks that may be the source of any nearby placer gold.

Eolian Gold Deposits

Prospectors who specialize in electronic detecting for nuggets in desert areas are especially interested in this type of deposit, as it yields nuggets that are close to the surface of the ground...

Associated Gold Placers of the Comstock

What many people don’t realize is that the Comstock Lode produced over 8,000,000 ounces of gold…

Subscription Required:
The Bawl Mill   • Ask The Experts—Iridium   • Ask The Experts—Highbanker legal in CA?; Best place to sell raw gold?   • Ask The Experts—Using classifiers   • So, Where's The Gold?—Finding Gold Detectors Miss   • The Oregon Claim   • Forest Service v. Michael & Linda Backlund   • Highbanking on the Feather River   • CFTC Finds Evidence of Silver Market Manipulation   • Gold in Arizona   • Detecting for Gold in Australia—The Kimberley Trip   • Melman on Gold & Silver   • Mining Stock Quotes and Mineral & Metal Prices

Legislative and Regulatory Update


Garrett Electronics - trusted by real miners & prospectors!
Precious Metals Recovery plants and equipment
Fighting to keep public lands open to the public
Specializing in the processing of precious metal ores!
Watch prospecting shows on your computer right now
Free Online Sample Issue