Sinking coins.....

[Roland58]

I know there is a formula that can estimate the sink rate of a coin in a given soil type and moisture rate. My question is, does a coin continue to sink, if otherwise left undisturbed? And, if so, how are the Roman coins and such found at such shallow levels? Hmmmm.

 

[fishbone3d]

I feel your pain. There are so many factors in the depth of a coin. I have found old coins almost on top, and 10 or more inches deep. It depends on vegetation decay, soil erosion, even moles and gophers just to mention a few. Tree roots also push coins upwards. Roman coins are found a lot in fields. Fields are disturbed by plowing. For example, I found a barber dime looking right back at me in a cornfield, no detector needed. Also think of arrowhead hunting in the states. Most are thousands of years old. Most are found in fields looking at you. Landscaping is also a factor, I have found memorial pennies over 7 inches deep. That is a bummer, let me tell you. It is all about the environment, and the soil that the coin is dropped in.

 

[Tuberale]

Unless your soils are supersaturated, as in quicksand, coins will not go lower in soils. That is myth.

However, over time, coins do become covered with soils.

A soil scientist at Oregon State University told me and others, soils "grow" in Oregon at the rate of about 1 inch per 200 years. So if you've looking at Roman times in England, could be aways down there.

Only apparent alteration to this are earthquakes and soil disturbance, such as plowing/farming, which can both raise and lower (mostly raise) coins toward the surface.

 

[Roland58]

Thank you, Gentlemen. I was under the belief that a coin would continue to "sink" over time, if otherwise undisturbed. The "growing soil" statement makes sense. I guess I'll just dig as far as needed to find one.

 

[Swartzie]

They are where you find them. The oldest coins I have dug have actually been the most shallow. Found a capped liberty half cent at less than 2 inches. King George II halfpence at 5 inches. That's just where the detector gods decided to put them.

-Swartzie

 

[diggemall]

If you are in an area (as I am) where the ground freezes every winter, frost heave tends to push solid buried items UP towards the surface. That said, I have dug coins as deep as 7 or 8 inches as well, in areas that have been largely undisturbed for decades. The effect of frost heave may be dependent on the size or mass / density of the object ? No clue.

Diggem'

 

[Ray S ECenFL]

I am sure there are a lot of factors to consider, but here is a basic rule of thumb.

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

 

[diggemall]

I am sure there are a lot of factors to consider, but here is a basic rule of thumb.

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

Hey, Ray. Not to poke holes in what otherwise sounds logical, but: So why then do rocks keep surfacing in farmers fields that have been under plow for literally hundreds of years ?

Diggem'

 

[Coin Digger]

I am sure there are a lot of factors to consider, but here is a basic rule of thumb.

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

I've read an article on that very subject some years back. A coin will sink until it's mass or density matches that of the surrounding soil. Outside factors such as freeze thaw cycle will effect how the coin reacts to it's surrounding environment.

 

[Ray S ECenFL]

I am sure there are a lot of factors to consider, but here is a basic rule of thumb.

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

Hey, Ray. Not to poke holes in what otherwise sounds logical, but: So why then do rocks keep surfacing in farmers fields that have been under plow for literally hundreds of years ?

Diggem'

That would be the other factors....

 

[diggemall]

I am sure there are a lot of factors to consider, but here is a basic rule of thumb.

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

Hey, Ray. Not to poke holes in what otherwise sounds logical, but: So why then do rocks keep surfacing in farmers fields that have been under plow for literally hundreds of years ?

Diggem'

That would be the other factors....

 

[MarkDz]

Excellent question and answers... I have to agree with people who say it's basically up to chance. I mean, within a few yards I've dug soda cans at 9 inches and 1700s coins practically on the surface. Crazy stuff.