Coins Sinking How Much per year?

[daddyflea]

This may have been talked about on these Forums for years. I just don't know. I have been detecting for many years and here goes my opinion. The Dirt really makes a difference and here we have just plain old coal Black dirt.

Left unchecked, I believe a coin will sink at least one inch every 6 to seven years.

In hard clay I believe this will at least triple or 1 inch every 15 to 20 years.

Opinions please.

 

[BarberBill]

You're right in that I've seen this thread several times on forums. I don't think there's any accurate answer generally, as there are too many variables from one location to another. Nice black soil, versus harder clay, versus wet (or dry) sand etc. etc. Then we could factor in weather. Is the location often covered with snow for months, is it bone dry most of the year, does the ground heave and shrink due to frost and so on. I'm sure a person could do a study on how this works in their yard or in the area near home if they wanted to go to the trouble, but it would only be valid for areas with very similar conditions.
Also, I've seen threads where some feel coins tend to be covered (over time) more than they sink by the build up of cut grass, falling leaves etc. Between these two theories I guess you can "pay your money and take your choice" as they say.
So - it's an interesting question, but hard to get a definitive answer.
My two bits
BB

 

[dewcon4414]

Physically most objects will sink to the depth of objects of equal weight..... UNLESS something stops them such as hard pan, roots, and trash. Like Bill said thou there is a lot of varibles... which includes rain, leaves, shifting of soil, density of soil, moving of soil by man.... on and on.

Dew

 

[Geo Unit]

And our "normal" weather patterns haven't been normal lately.
So I think that they sink some, get covered some and do whatever else Mother Nature wants.
I actually tried to figure this out based on readings, finds and gut feeling and came up with about an eighth inch (give or take) per year.
Then I dug a 1905 IH at 6" and a 1911 wheatie at 8".
But when were they lost?

 

[Oak]

It was an 1893 commemorative half dollar. The reason I know it was lost for 40 years is that a friend of the family lost it when I was a child.

HH

 

[Ray S ECenFL]

It goes something like this:

An object will sink until the density of the material surrounding the object equals or exceeds the density of the object.

This does not take in the rate of the sinking but just the fact that it will continue to sink until the density of the surrounding material equals or exceeds the density of the object.

The rate of decent is dependant on the weight, size and shape of the object in relation to its density and the density of the surrounding material.

Other factors that affect the density of the surrounding material are heat, cold and dampness.

 

[Larry (IL)]

I have to agree with you Bill, too many reasons why coins are where they are. I have seen one study that objects don't "sink" into the ground, they are covered up with wind blown dirt, decomposing leaves and the like. I'm sure the weather, moles, worms, foot traffic and hundreds of other factors affect the "effect" of coins sinking.

The one thing I'm sure of though is that coins don't just sink into the ground without having some kind of help.

 

[BarberBill]

Yep, something puts them under the surface.
BB