Monday, August 3, 2015

8/3/15 Report - Layers of Sand Holding Coins. Classification Of Objects On A Beach. Hurricane Vulnerable Cities.

Written by the TreasureGuide for the exclusive use of

Beach Illustration.

The thing that I want to point out using this illustration is the layers shown both under the shallow water and under the berm crest.

You can sometimes clearly observe different layers of sand when you dig a target.   You'll see one color of sand over another.  Sometimes the different layers are the same color but one layer will be more course or fine than the other layer.

There are times when coins and things wash up with sand.  When that happens, the coins will be in that layer of sand.  That layer can then either get covered up by newer layers or eroded away.

Once you find a coin in a layer of sand there will probably be others in the same layer.  You can then  look for the layer containing the coins.  That layer might be covered by other layers or exposed by erosion.

So when you find a coin that has washed up, pay attention to the type of sand it was found in.

A lot of times I've dug coins that were right at the dividing point between two layers of sand.  I've found that a lot.


How are birds and treasure coins alike?  They flock together.

You might remember me saying this before.  Birds of a feather flock together.  So do treasures.

When you find one of a particular kind, there is a good chance you'll find more around the same area.

That was demonstrated very well this year when the guys on the salvage boat Capitana found hundreds of musket balls.  They went many days without finding any, then all of a sudden found hundreds together.  It wasn't an accident.

The longer things have been in the ocean and the more they have been affected by moving water, the more they are classified or grouped together.  One of the most repeated myths of treasure hunting is that items are classified by weight.  As I've said before, a ton of Styrofoam will still float, and so will an ocean liner made out of steel.  It isn't weight so much as it is density, and also, by shape.  In my opinion both of those are big determinants of how items are classified by moving water.

Things that are recently dropped or are dropped on the high and dry beach won't be sorted.  It takes time and force.  So the longer things are exposed to more force the more classification you will see.

It is a lot easier to learn about classification where a lot of targets are lost.   Where there are few targets you won't see the patterns nearly as easily.  I was fortunate to be able to quickly learn about classification when I first started detecting in South Florida where you have a high population density of beach goers.

Objects don't have to be identical to be grouped or clustered together.  They just have to be similar - in density and size and shape.  The more similar they are the more they will tend to cluster.

People often don't take shape into account, but shape is important too.  I've talked before about how different shaped objects move differently.  I've even reported my own experiments.  Using a splash test, I predicted how different size and shaped sinkers moved different amounts when hit by splash of water.  Round objects moved more on a sand surface than flat coin-like objects of the same density and weight.  When objects are the same density and shape, larger and heavier objects were moved less.

There are also objects that trap air.  Those are mostly more recent objects such as watches, for example.  Watches move easily and tend to stay in higher and looser sand because the trapped air makes them act as if they are less dense.  The bands, if still present, also affects how watches move in the water.

Of course, sometimes items are found together because they were lost together, such as coin spills.  Take a look at items found together to see if you can get any idea about how long ago they were lost.  Corrosion or patinas will sometimes give you some idea.

If you find an item take a look at it to see if it provides any clues.  If it looks like it was lost a good time ago and has been subject to moving water, be sure to look for other similar items in the same area.  That is one of the main things you can do to hunt more effectively and efficiently.  Get as much information out of finds as you can.

When you see one Robin, there is a good chance that there will be a flock.


If you find a medallion take a look at the edge of the medal.  Often you'll find helpful markings there.

Medallion Showing Marks On Edge.

Here is a listing of the cities or towns that are most vulnerable to hurricanes.


The Treausure Coast will have another week or so of one to two foot surf, so no big changes.

Happy hunting,