How To Find Lost Mines

At the beginning of summer, when the temperature was I l20 in the shade, Clarence Thomas and I began searching for a lost silver mine in Arizonas Silver District. To reach the district, we had to make our way up 14 miles of bad road in a four-wheel drive. When we finally arrived, what we found surprised us: Oretech, a Cana­dian mining company, had rebuilt all the old jeep roads, bulldozed out new ones and drilled hundreds of test holes and dug dozens of trenches throughout the district.

Oretech is an old-line firm on the Canadian Stock Exchange. Report­edly, they spent a half-million dol­lars on geo-chemical exploration of the district just prior to their annual stockholders meeting. Oretech was searching for mineral reserves large ore-bodies of heavy metals, such as lead and silver on the off chance that market conditions would improve for these metals.

Oretech collected thousands of soil samples from test holes, trenches and abandoned mines throughout the district. The samples were shipped to the home office for whats known as trace analysis, which is a geo-chemical prospecting method that uses a sophisticated instrument known as an atomic absorption spec­trophotometer for the chemical analysis of heavy metals in the parts per million and parts per billion range.

Oretech must have been at least partially successful in their search as they made long-term lease agree­ments with the owners of both the Dives and Clip Mines. But did Oretech find the lost mine Clarence and I were searching for, the Lost Mendivil Silver Mine? After all, geo-chemical prospecting is the per­fect method to use to find a lost mine. The Lost Mendivil Mine is supposed to be located just east of the Clip Mine near an old cattle trail.

But you neednt win the lottery to finance an expedition to search for your favorite lost mine. You can use relatively inexpensive geochemical prospecting methods. You need only learn how and where to collect soil samples, then send these samples to an independent laboratory for trace metal analysis via atomic absorption spectroscopy. One such lab is the Metallurgical Research & Assay Laboratory, located in Henderson, Nevada, which is owned and oper­ated by Dr. Jordan. You must also learn how to interpret the results. Sounds easy, and it is!

First, study the waybill to the lost mine youre seeking to determine its approximate location. If the gold mine you researching for is really out there, the chances are that a part of it has been weathered away by Mother Na­ture and this erosion has left a trail of gold particles that are detectable by atomic absorption analysis. This trail is often detectable up to a mile away from the lost vein you are looking for.

The old-timers used a gold pan to follow similar trails to their source, but they counted on finding gold nug­gets to lead them to a mine. Today, however, atomic absorption methods make it possible to measure the gold content of soils in the parts per mil­lion and parts per billion range, which makes it possible for you to find a lost mine.

According to Paul Jones, a regis­tered professional geologist and min­ing engineer in the State of Idaho, It makes no difference whether man or Mother Nature has cleverly concealed the old outcrop or mine workings with a new layer of debris, that an­cient trail of gold particles is still there in the canyon (where you are searching) and can be rediscovered today.

So youve decided to search for a specific lost mine. The next thing you need to do is to make sure that the area you have selected for your search is open to prospecting and mine devel­opment. If its on private property, contact the property owner and se­cure permission prior to making your search.

The lost mine you are seeking may, of course, be found through the use of a metal detector; that is, if the weath­ered material surrounding the lost mine is in the form of nuggets. For Chet Long, a well-known Arizona based prospector, it took two entire summers to find a lost mine he and his partners had been searching for in the hot, dry mountains of Mexico. Chet and his buddies used metal detectors, dry washers and gold pans in their search for that mine.

At the end of the second summer, Chet had just about given up he when found a trail of nuggets in a canyon that led to a hidden mine. Inside the old mine, Chet found the second largest nugget ever found in Mexico: a 16-inch long, boot-shaped, chunk of gold that snow on display in a Mexico City bank. The mine had been abandoned 200 years earlier and, until Chet found it it had been a lost mine. Chet also found many smaller nuggets buried in wet clay inside the old mine. Some of these nuggets were as large as silver dollars!

To find your lost mine, youll need to sample soils and streambeds those with running water and those dry streams in the desert near the site where you suspect the lost mine is located. The initial reconnaissance of the area should include the collect­ing of stream sediment samples ev­ery quarter mile along all the can­yons and their tributaries.

The sampling process is quite simple: collect about one cup of sur­face material (dirt and sand) that moves down stream after a heavy rain. The material can be collected from either a canyon with running water or from any desert dry wash or canyon it makes no difference. Dis­card the course portion using a kitchen sieve, then send the rest to an independent laboratory with the fa­cilities to detect parts per billion in gold. Each sample you send will cost you about $10 to $15. Be sure to assign a location number to each sample you collect and place these numbers on a map.

These first few samples will show which drainages contain gold and which portions of the canyon de­serve a more detailed examination.

Once you have found an area that contains abnormal amounts of gold, go back to that area and lay out a grid of soil samples along the slope of the canyon. To keep your costs low, maintain your sample spacing at 200-foot intervals on the initial grid. Later, when the sample analy­ses are returned, you can follow through with closer sample spacing in the area of the best sample.

Other deposits that contain less gold, yet still give high heavy metal values in the soil often surround gold mines. As a result, you may have to check out a number of hot areas before finding your lost gold mine.

When Paul Jones, the professional geologist from Idaho, retired, he took up searching for lost mines as a hobby. For one reason or another, Jones headed for Mexico, where he found a new vein of rich gold ore in an old mining district using geo­chemical prospecting methods.

Jones used a variation of the soil testing methods described above: he used what he calls an indirect field test that measures parts per million total heavy metals. Heavy metals, such as copper, lead, silver and plati­num, are usually found with gold. Jones found this method much faster and cheaper than sending samples to a laboratory to measure parts per billion of gold.

The obvious advantage is having the results immediately available. Using this method, Jones found a vein of rich gold ore only a hundred yards from the famous Cerro Prieto Gold Mine, which was one of the largest gold producers in the State of Sonora, Mexico.

If you wish to contact Paul Jones, you can write to him at: P. 0. Box 6284, Nogales, Arizona 85628-6284. He wanders up from his mine in Mexico once in awhile to pick up his mail.

SOURCES:

Braun, Robert. Introduction to In­strumental Analysis. McGraw-Hill Book Company. New York. 1987.

Jones, Paul L. Lost Gold Mines Can Be Found. Gold and Treasure Hunter (a bimonthly publication for members of Modern Gold Miners and Treasure Hunters Association). October, 1993.

Weight, Harold 0. Lost Silver in the Trigos The Lost Mendivil Mine. Desert magazine. May, 1957.