Monday, July 20, 2015

7/20/15 Report - Alternate Methods To Metal Detecting. Air Lift Dredge. Silver Rosie dimes. History of Shipwrecks Book.

Written by the Treasureguide for the exclusive use of

90% Silver Rosie

Metal detecting isn't the goal for most of us.  The goal for most people is finding things.  Metal detecting is just the method.

Sometimes people act as if metal detecting is the goal, but we shouldn't forget that there are other methods for finding things.  Sifting, dredging and eye-balling are a few examples.

There are times when other methods will pay off, and there are times when metal detecting just won't work.

Other methods might actually be the best choice in some situations.  One would be when metal detecting isn't allowed.  Another would be when valuable objects are not made of metal.  Another might be when there is too much overburden or junk.

There are times when you can eye-ball coins and things somewhat effectively.  For example, when a strong wind has scoured a busy dry beach.  I've done that.  You can find a good number of coins by eye-balling.  Or when there has been erosion at a good spot where coins and things are being uncovered in front of your eyes.  Or along streets or curbs.

There have been places like that where I have found a good numbers of coins.  While you obviously won't find buried coins by eye-balling, you can find uncovered coins, and in some cases you can follow up with a detector.

Eye-balling can be the first step in narrowing down where you want to spend your time detecting.  If you find a coin or two that has been just uncovered along the surf line that is a place to check with a detector.

A good thing about eye-balling is the ease of quickly scanning large areas.  It works best in busy areas where there might be high concentrations of targets.

You might eye-ball for bills along a fence line after a carnival, for example.  Or along a sea weed line.

I know of one dip in the water off of a busy resort where bills tend to collect.  Snorkeling for bills often produces a few ones, fives or twenties.

In my 6/15 report I posted about how Russ P. does some sifting sometimes when he doesn't have a promising detecting spot.  It is a lot of work, but can be effective in the right place and has the advantage of being able to uncover non-metallic targets as well as metallic.

One thing you might consider is an air lift dredge.  It is only for those who dive though.

Here is an illustration.  It isn't too hard to construct an air lift dredge and it can be used to lift metallic as well as non-metallic items.  Of course it is easier to buy than make if you have the money.

I believe the Fisher organization used an air lift dredge in areas known for emeralds.

The illustration shown here and the excerpt below is from Wikipedia.

Typically, the airlift is constructed from a 3 metre to 10 metre long, 10 cm diameter pipe. A controllable compressed air supply vents into the inside, lower end of the pipe (The input end always being the lower end). Compressed air is injected into the pipe in one to three second bursts with an interval long enough to let the resulting bubble to rise to the higher, output end of the pipe. The bubble moves water through the pipe sucking debris from the lower end and depositing it from the upper end of the pipe. Ejected debris can be either cast off (as in simply removing oveburden) or collected.

Here is a YouTube demonstration..

Two problems with air lift dredges is that they are most effective in deeper water and are not easily moved.  A small gas powered dredge would work in shallow water.  Keene is one well known manufacturer of portable gold dredges.

There are other methods that I haven't yet discussed.  Some much less expensive and easy to construct.  I just wanted to make the point that metal detecting is not the goal, and that there are plenty of other techniques.  Also that there are situations when other techniques might even work better.

Of course, you can use different methods in combination too.  The bigger point is to keep thinking.

What inspired me to write this today is that I've been using some alternative methods lately but want to get some good pictures and record results before I post about them.  Just like with metal detecting, sometimes they don't work out real well, but sometimes they do.


I ran across a book you might want to take a look at.  It is History of Shipwrecks by Angus Konstam.
You can preview it free online.  Click on the underlined title above to go there.


Here is something to watch for even though it would be rare to find in circulation.  Starting in 1992 the San Francisco Mint  produced some 90% silver Roosevelt dimes, though all such silver dimes have been struck in Proof format.  A 2004 S dime would have a melt of around $1.00 and in mint state sell for around $6.00.


The Treasure Coast predictions are for a two-foot surf next Monday.  Normally I wouldn't pay any attention to that, but we haven't had anything that big for weeks, if you can believe that.  I never thought I'd see the day when a two-foot surf looked like a bump up.  It might not even happen.

Happy hunting,