Written by the TreasureGuide for the exclusive use of the Treasure Beaches Report
Lead Balls Found Made by the Capitana Crew in 2015 as Submitted by Captain Jonah. |
Occasionally I like to look back. Here is a find of lead shot. Hundreds of pistol and musket shot. When I saw it I felt they were getting close.
This group of old shot was found ten years ago and posted on 7/25 ten years ago. There were other finds that day as well.
I felt that something more shiny was going to be found next and struggled for days after wanting to say it in a post but didn't. I thought it was analysis back then - putting two and two together. I had found lead finds leading to gold so often in my own experience. I mentioned the association between lead and gold in several old posts.
One incident that imprinted the association in my mind was a time I found a big heavy class ring (a full oz.) in a hole after removing some sinkers of the same weight. They were all concentrated in an area of about a foot, and maybe a little more, square. It was just that one little hole in a shallow water area with not much of anything else around. So it made a big impression that was reinforced in my experience many times later.
There is more to it, but the association between lead and gold is in part due to the density, but the density of pure silver is closer to that of lead than lead and gold. Gold was for a long time my primary marker of a successful hunt so I paid a lot more attention to that than silver, as you may have noticed from my old find photos.
I previously posted some charts that give the density of a variety of metals. This one is better than some of those.
Notice particularly those metals at the bottom of the chart, which are the types of things often targeted and which also have the highest densities. Copper and silver both have a lower density than lead and gold is considerably higher.
Of course, there is more to the relationship of lead and gold in the field. As I've said many times, a beach is a dynamic system. Many factors influence where things end up. For example, where they are originally lost and the amount of time that has elapsed since being lost are obviously important factors. There is also the matter of the shape of the items as well as other factors, but first I want to get into something else that is very important.
Detectorists often talk about heavy items sinking more on a beach. First it isn't so much about weight as density, and secondly, it isn't so much about sinking as it is about being covered or settling. I won't go into the details of the distinctions, but, as I've said before, a ton of Styrofoam won't sink whereas a cruise ship weighting many tons will float. It isn't about weight.
If you've been reading this blog very long, you know the importance the force of water, suspension points and drop points. That is a fairly complex topic, but one I've addressed multiple times in the past.
Generally speaking, it takes relatively little force to move sand, and more force to move other things with a higher density. We've had very small surf lately, and during those conditions the beaches accumulate of build as the water pushes sand up onto the beach. But the amount of water force is way too small to push things like rocks or coins up onto the beach.
I once posted a little demonstration that shows how objects of the same density, but various shapes were moved by moving water. (The Treasure Beaches Report Direct From Florida's Treasure Coast.: 8/5/13 Report - What Actually Determines How Obects Move On a Beach Or In the Water.)
... of the four objects that were previously in a line. The egg-shaped object moved the farthest, followed the fish-shaped sinker, then the lighter disk, and then the larger disk, which was moved the least by the water.
So. for objects having the same density, shape matters. Some objects present more surface area for the water to push against, such as the egg-shaped sinker, while other lower profile objects, such as the coin-like sinkers were moved less.
The egg-shaped sinker also rolled. It moved more easily and farther.
How many times have you seen a ring or coin roll down the slope of a beach. I've seen it a lot of times.
I won't make much of the demonstration because, it wasn't a very good experiment, but the results were in line with my personal beach observations and reasoning, which predicted very similar results.
The main point I'm making here is that it is not just density that determines how much a given water force will move an item. Coins are low profile. You might say they are more hydrodynamic as they lay flat on a beach and the water passes easily around them. They can move other ways in particular situations though. Sometimes, for example, they will flip or step down a slope.
Let's say it is a day with very small surf. It might still be enough to push a little sand, but not an item like a coin. The coin remains stationary while sand washed up over it. If, however, there is a stronger wave, it can move the coin as well as the sand. It becomes a matter of the relative movement. A lot of sand can be moved away while the coin lags behind.
Of course, that kind of thing happens over and over at the base of the beach and in the water. Every wave can have a cumulative effect.
There is too much to explain it all in a single post, but hopefully you get the idea.
Over time, items with similar densities will tend to be distributed according to the forces acting upon them and over time they will tend to be distributed in patterns and gather in certain areas. The longer they are out there. The tendency for denser items in general, is to settle over time in low areas where they will remain until and unless some larger force can move them.
So what I am saying with all this is that I've observed in the field the frequent association of lead and gold and was getting the feeling after this find that gold was likely nearby. I say "feeling" because it was a feeling rather simply reasoning or analysis.
I took a long detour to explain my feelings on that day, but actually what I mainly wanted to do highlight what was going on ten years ago today.
Lead wasn't all that Captain Jonah and the crew of the Capitana found that day. Here is a photo of some more of their finds.
More Capitana Finds From Ten Years Ago Today. Photo Submitted by Captain Jonah Martinez. |
As you can see some really great finds were being made in addition to the numerous lead balls shown above. You might consider these finds much more interesting as finds, but what struck me that day was the lead balls and the feeling of more to come.