Scratching your silver

[kak]

Hi everyone lucky enough to dig silver,
I read many comments about not rubbing a freshly dug coin to see the date because it might scratch the coin. This would also apply to cleaning the coin at home. Is this just a precaution to adding more damage? Was the coin naturally polished while in the ground and clearly shows new scratches or is it already in bad enough condition from being in the ground for a long time? If so then how would anyone know whether the coin was scratched after digging or before it was even dropped?
Thanks,
kak

 

[dave5710]

It probably isn't the dirt that scratches the silver coins, it is the tiny grains of sand and grit in the dirt. If the date isn't visible straight out of the ground, pour a little water on it from your water bottle. If you still can't read it, some folks carry a film canister or similar small container(plastic) with water and a little dish soap in it. Shake a little and look again. If that still doesn't do the job just be patient until you get home. The date will still be the same I'll betcha. Just don't rub the coin and slid those little grains of sand back and forth across it. Scratches will lower the grade of the coin. A hundred dollar coin could become a twenty dollar coin will quick. At home I usually blast the dirt away under the faucet. In my Central Illinois soil, good black dirt, silver isn't polished naturally, but tarnish doesn't occur either. Although silver I have found in clay and sandy dirt do show some tarnish.

 

[UK Brian]

You just devalue your find more whatever its made of. Collectors like to see a patina on a coin. Though the coin may have become worn in circulation and then some surface scratches occur as it settle in the ground a patina does develop in almost any soil given time. Scratch through the patina and it can't be fixed (you can buy chemicals to resurface but its not the same).

A dealer or auctioneer's list may indicate that a coin has been cleaned and a much lower price can be expected. Light polishing reduces value, heavy polishing destroys.

Same with "halo" effect that so many seem facinated with. If a coin has developed enough halo to aid in its finding then its not a collectable coin unless an extremely rare specimen.

 

[edjcox]

Coins are composed of many metals. Coins can be silver, gold, platinum, copper, bronze, nickel coated, aluminum, steel and stainless steel, and bi-metals in combinations of the foregoing metals. So if a coin is placed in the ground the minerals of the soils, water, acids and bases formed all will attack the metal. Depending on the metal and the soil the coin will deteriorate with the exception of gold coins unless they are mixed metal golds. Surrounding the coin after a good long while in some soils and after short times in others will exist a small leach field of metals leached by the acids and bases from the coin. This is what is called the halo. It doesn't occur everywhere, it doesn't occur with all coins at the same rate. Some metals just don't produce one. The in situ environment of the coin and soil determine it.

So if you come along with your detector and that EM field flashes down through the soil and comes in contact with this layers of leached conductive metal in the soil surrounding the coin and the moisture conditions are right, etc, your detectors EM field will conduct along the halo soil and will be detected by your coil. The amount of conductivity varies with the soil, the metal, the moisture level, etc. It's highly variable and will not ever be consistent. Obviously a metal halo around a coin increases the probability of detection.


Hopefully this might explain halo a bit.

 

[UK Brian]

Nothing to do with "Kak's" question but I'm glad you have confirmed what I already said. Halo may allow most metal items to be detected deeper but its hardly worth digging them as they will not be collectable.
Re gold ....there is the possibility of more depth on pure gold due to action/reaction between the gold and an adjoining more active "sacrificial anode" though electron and anode pathways are required to form a closed circuit.

 

[Dan-Pa.]

Find a valuable date coin simply put in a seperate container and take to your coin dealer for evaluation as they will clean professionally. 9 out of 10 times have a novice cleaning a coin will devaluate it big time..If you must get the dirt off to see the date etc. simply run under some cold water when you arrive home with no rubbing..
Silver coins usually hold up well even being buried for years but copper and silver usually do not in most cases..