Wednesday, June 4, 2014

6/414 Report - Half Cent, More Glitz, TV Treasure Hunt, Queen's Coach & Three Characteristics of Metal Detector Signals

Written by the TreasureGuide for the exclusive use of

Find and photo by Steve S.
Steve S. is from Iowa, but like many detectorists, visits the Treasure Coast where he does some metal detecting.

Here is how he found this half cent.

He said, Went out last Sunday to a nearby village and detected a residence built in the 1840s. This 1829 Half Cent was all that I found. Nice shape for Iowa.

That is a very nice find.  In uncirculated condition it would be worth well over two hundred dollars.

Congratulations Steve!
Photo of find by Steve S.

Half cents are rare finds.

Here is a web site that discusses and gives values of half cents.

NBC's Today Show has been having a daily treasure hunt.  They hide an envelope containing prizes in the city of the day and then give clues to where the envelope can be found.

The Queen of England got a new coach.  It is Covered in around 400 books of gold leaf, it contains timbers from king Henry VIII's flagship the Mary Rose, which sank in 1545, and Isaac Newton's apple tree, which inspired him to form his theory of gravity.

Here is the link for more about that.

Timbers from Henry VIII's flagship!  Is that saving history for the public?   Maybe it is.  Doesn't seem the best use to me.

Find and photo by Robert H.

I've been showing some of the finds of Robert H. lately.  I posted his trash finds one day too when I was talking about how much trash is picked up by detectorists.

Here is another one of Robert's finds.  This one is really glitzy!

Congrats Robert.  

A few posts ago I was talking about signal detection theory as it relates to metal detecting.  I talked about how signals usually exist in a field of noise.  I wanted to talk a little about three features of good signals when you are using all-metals or pin-point modes.

First, of course, is loudness.  Obviously a loud signal will tend to stand out, but not necessarily, if you have a lot of noise, including a very rough threshold or poorly ground balanced detector.  Increasing volume can increase noise as much as the signal and therefore won't necessarily be of much help.

Signal loudness, when considered in conjunction with other variables, can tell you something about the depth, size and composition of a target - even in all metals mode.  Of course shallow targets will tend to be louder.  Larger targets will tend to be louder.  And more conductive targets will tend to be louder.

Distinctness is another quality of a signal.  Signals will be more distinct (have a more sudden onset and termination) sound, when the target is more shallow.  Distinctness will generally make a good signal easier to identify in a field of noise.  However, as the target gets deeper the signal will appear more smooth.  It will not be as loud and will not be as distinct.

A third signal quality is duration - how long the signal remains loud as you sweep your coil.

You can get a very good idea of how shallow a target is by combining these three signal characteristics.  A small target near the surface will be loud and distinct.   The duration of the signal will, however, vary depending upon the size of the target.  Duration and distinctness, as I've defined them are different things.

A deeper object of the same size and composition will produce a signal that is not as loud and not as distinct.

A larger object of the same composition at the same depth will produce a signal that is as louder but the signal will not be as distinct, and the duration will be larger (The signal will be more spread out.).

If you sweep multiple times over an object in all metals mode and vary the direction of your sweep, you can get some idea of its size and shape.

One peculiarity that I've talked about before is the double signal produced by narrow long objects such as nails when you sweep in one direction and single beep when you sweep at 90 degrees to that.  I've gone over that in detail in the past.

With practice you can use your detector in all metals mode to gain a lot of information about suspected targets from the loudness, distinctness and duration of the signal.

Back to the signal in noise problem.  Signals giving faint signals are more difficult to detect in noise, as are signals that are less distinct.   Faint indistinct signals will often be lost in noise such as that created by black sand and salt mineralization or even an erratic threshold tone, however you can easily detect near surface objects in black sand from the more distinct signals. 

Learn to understand what your detector is telling you.  It might be saying more than you would guess.

I showed a photo of two detectorists on a beach a day or two ago.  They wrote in.  The detectorists are Tim and Betty M. 

Thanks to all of you who write and submit finds and information.  I really appreciate it.

On the Treasure Coast the surf today is three to five feet.  The surf will be decreasing the nest few days and we'll be back down to something like a two foot surf.  Don't expect any improvement in beach conditions.  The tides are pretty flat now too.

Happy hunting,