9/5/14 Report - Gold Cob Found By Salvage Crew On Treasure Coast! Fascinating Clump of Artifacts Too. How Objects Sink In Dry Sand.

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Gold Treasure Coast Shipwreck Coin
Photos submitted by Captain Jonah Martinez

The past few days I've given a lot of information on how objects sink on the beach, and I'm far from done with that.  I've only addressed a few factors so far and will continue with that topic in the future.

Today I wanted to take a bit of a break from that and show you some finds to drool over.  The finds were made by the crews working the shipwrecks off of the Treasure Coast.   Thanks to Captain Jonah Martinez for sending the pictures.

First, here is a gold coin they found.  Although this gold coin sure is pretty, they found a silver coin that actually might be much more rare.

I'm no expert on Spanish shipwreck coins - far from it.  So if you can correct anything I say here, feel free.

Notice the type of cross on the top photo.  Each arm of the cross is like a cross on the end.

That is not a real common type of cross, but that type of cross was used on some Mexican escudos,

On the left side of that coin, I think I can make out part of the "M" mint mark for Mexico.

I can not see the legend on this coin or the date.  They do not appear to be present.




Below is a photo of what I believe is a very similar escudo.

It is found in Monedas Espanolas desde Juana y Carlos a Isabel II 1504 a 1868, by F Calico et al, 1985.

Illustration of Similar Design Escudo from the Calico et al Book.

The following illustration more clearly shows a similar type of shield and the same type of cross although there may be some differences.

Illustration of Similar Escudo Design Elements.
Source: Cobs, Pieces or Eight and Treasure Coins book by Sewall Menzel

From what I've seen I would guess the escudo above to be an early 1700s Mexico two-escudo.  That is just m guess from what I can see from the photo.


Below are two pictures of a recovered clump.   Captain Jonah says this clump of objects was found by Mike and Gavin and ... if you look close you can see to buckles, two medallions, a silver spoon and maybe cuff links...

Photos submitted by Captain Jonah Martinez.

I always find clumps exciting.  You never know what all might be in them.  And I never know if I want to leave them alone or take them apart to find what is in them.  There is that conflict between wanting to preserve them and wanting to find out what might be in there.

They can be x-rayed or examined internally by using other technologies without taking them apart.

Those are just a couple of the photos that Captain Jonah sent me.  I'll show more of them in future posts.  Included are cobs, porcelain, and one very early and exciting cob.

Thanks for sharing Captain!


The last two posts that I did received  lot of +1s.  It seems they were very much liked.

I should explain that the did not discuss all relevant factors, but maybe it did help to put to rest some common misconceptions.  I still want to add just a little to that discussion today.

First of all, people might wander how objects sink in dry sand where the water does not hit if objects only sink through suspended or disturbed sand.   One big factor affecting dry sand is the wind.  Barrier islands and beaches in general tend to migrate away from the ocean as wind coming off the ocean tends to blow sand towards the back beach where it piles up as dunes and fills in marsh land.  You can find that fact in any number of books.

On our local beaches I've seen a lot of dune building over the past year.  Any plants or anything that serves as a wind break will cause wind driven sand to drop off and build up.  That causes items lost on the dry beach to be buried as the sand builds up.

If you go to the beach after a busy holiday, you'll notice how much the busy spots have been churned up by foot traffic, kids digging, etc.  That certainly disturbs the top layers of sand and causes items to sink or get covered.

Also, the water does occasionally come up over the dry sand and all of the way to the back dunes.

And they sink in when dropped, flung or thrown.

There are some ways that the dry sand is disturbed causing things to sink or get more deeply buried in the dry sand.

I'll discuss more details on how items sink on the beach and in the shallow water in the future, but I'll also be showing some more pictures of the Treasure Coast treasure finds that Captain Jonah sent me.


We still have a one to two foot surf on the Treasure Coast.  Beach hunters are tired of the consistently smooth surf this year, but it has been good for the salvage crews.

There is one disturbance coming off of Africa, but it is days out, and we'll have smooth water on the Treasure Coast for at least several days.


Happy hunting,
TreasureGuide@comcast.net

3/10/14 Report - Experiments On The Movement Of Sand And Other Objects On A Beach

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

I'm sure everybody had a great time at the TCAS club hunt this past weekend.

To the left is a picture of the beginning of an experiment.

Three lead sinkers were placed on a sand bar in shallow water where the water would get deeper as the tide came in.

At the time of placement the objects were in very calm water.  What I'm talking about here today happened before the water got rough.

Which object do you think would be the first to disappear from view while the waves were still gentle?

The big heavy one?  The little round one? Or the disc shaped one.

This might or might not be a surprise to you.

It was the disc shaped object that disappeared first.  It disappeared quickly and well before either of the other two.  The heaviest appeared to remain the most visible in those first minutes before the water got rough.

Some sand was removed from around the two egg shaped sinkers making a little depression around them, but the disc shaped one disappeared very quickly.

People often talk of things sinking.  And they talk about heavy objects sinking more.  That isn't always the case.

I should make one clarification here.  When I just said sinking, it was as much a matter of being covered as sinking.  There is a difference.

There is what I'll call a trigger point.  It takes a certain amount of water forced to move different objects.  Sand will be moved before the sinkers.

Very often when people think that things are sinking on a beach, they are actually being covered.

The trigger point is critical.  It is one of the factors that helps to create coin holes and lines.

There is also a trigger point or threshold of force that determines when an item will be dropped or settle out.

Considering the change in waves and changing tides etc. different items will be moved and dropped at different times.

In the first few moments of the experiment above the sand was being moved, not the objects.

When the sand moves objects can sink as they settle down as the sand is removed from under them or when they are pulled down a slope.

 I was flipping through TV channels the other day and happened to hit a program on USOs (Unidentified Submerged Objects, or something like that).  They were trying to find a plane that wrecked in the water off of the California coast and couldn't find it where they thought it would be.

In order to try to figure out what happened to it they did a little laboratory experiment.  I don't think it was a great experiment for what they were trying to accomplish but the experiment did reveal one thing.

I tried to find the video clip online but couldn't so I made the following diagram.  If you can find the clip I hope you'll send me a link.

They had a big tank of water and a sloped surface in it covered with sand.  They put what looked like a sinker on the sand.  The sinker was partly in the sand but mostly exposed.

They then toke a hose and made a current aimed at the object and up the slope.

Guess what happened to the object.

The current pushed the sand away from the front and sides of the object as the water rushed around it.  The object then STEPPED down the slope.  I say "stepped" because it moved in small quick steps, pausing in between steps.

The current moved the sand from the front of the object but not the back of the object.  Gravity on the object and also the sand behind the object then moved the object down the slope.

The current trigger or threshold level was sufficient to move the sand in the current up the slope but gravity moved the object down the slope.

That was a good illustration.

If you start putting all of these things together you will understand how gold and cobs and things move on a beach.  It isn't simple though.  There are many factors.


On the Treasure Coast we have beautiful weather again today.  A lot of sand though!

The wind is out of the West and the surf is only around three feet.  It will decrease even more for a couple of days.

Happy hunting,
TreasureGuide@comcast.net