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Beware of Defects on Coins

Beware of Damaged Coins. Image: CoinWeek.
Beware of Damaged Coins. Image: CoinWeek.

By Peter Mosiondz, Jr. for CoinWeek …..
A defect is a defect no matter how slight the seller proclaims it. And that same “slight’ defect will become much more severe in the eyes of a buyer when it comes time to sell or trade that same coin. Try to remember this fact of life in your coin collecting journey.

This sage advice was drummed into me by my late philatelic friend Herman “Pat” Herst, Jr.

No matter how the seller describes the coin, if it has a defect other than the normal bag marks one encounters, then it’s a defective coin. This in spite of the protestations that said defect is “tiny” or “insignificant”, as some are wont to say. That “microscopic” scratch will turn out to be a gouge when it is time to part with the coin. Take my word for it as a dealer and a collector for half a century. It always pays to buy a nice defect-free coin. The value of any coin possessing other than mint-made blemishes is reduced significantly.

Scratches are one thing; bag marks are another.

The former are caused by improper handling or cleaning. They are commonly caused by abrasive material coming in contact with the coin’s surface. Perhaps they originated with a brush or some other tool that was used in an attempt to improve the appearance of the coin. Possibly there was a failed attempt to remove some dirt or corrosion. Or maybe the coin was dropped on a hard surface. There are other ways in which scratches may result. These examples are the ones ordinarily seen. Whatever the reason, the coin is damaged.

Bag marks, on the other hand, are mint-made and therefore very natural. They are the result of a coin falling from the coining press into a bin with other coins of the same denomination. Then the coins in the bins are bagged, creating another situation where they are clashing one against the other. Finally, as the bags are moved from one location to the next, additional contact is made.

An experienced and trained eye will be able to easily distinguish between a man-made scratch and a bag mark. If you are in doubt, visit your friendly neighborhood coin dealer and ask to be shown the difference. Anything mint-made will not be a factor in the price unless the bag marks are very severe. I have seen some Morgan silver dollars that were so heavily bag marked that Miss Liberty seemed to have a bad case of chicken pox. An MS60 silver dollar may show numerous and possibly unattractive bag marks, but then again, if it’s properly graded, then the asking price should be commensurate with the coin’s appearance or “eye appeal”.

You may encounter the term “dig” as a descriptor of a bag mark. This is not necessarily so. A dig is most usually the result of one coin’s edge banging into another coin’s surface and producing what at first glance may resemble a pronounced bag mark. It is, as the name implies, a “dig”. Nevertheless, it is still mint-made and the price should reflect this fact.

A Stone Mountain half dollar with large scratches on the obverse.“Rim dings”, or dents on the coin’s rim, could be either mint-made or man-made. For example, in the early days of coining, the large cent planchets were not perfect and these “dings” were not uncommon.

A “dent”, on the other hand, is the result of someone dropping the coin onto a hard surface. No matter how slight the dent looks to you, it is still a defect and worthy of a significant price reduction if you choose to purchase the coin. Beware also of someone describing a dent as a rim ding.

Speaking of large cents, it is important to note that the metal composition of copper coins is prone to attract carbon spots or verdigris. For the most part, the carbon spots are attributed to moisture coming into contact with the coin’s surface. This is considered a defect. You may be told that carbon spots are natural in copper coins. In that case, seek the unnatural copper coin. Verdigris, or corrosion, is a serious defect and usually observed in copper coins.

A commonly seen situation, especially with uncirculated coins, is that of artificial toning. This is an attempt, usually very transparent, to make some sort of attractive “rainbow” colouration or other colour effect. This method is sometimes used to cover a defect such as a dig or scratch. “Dipping” is another prevalent method of trying to enhance a coin’s appearance by making it brilliant.

A quick way to determine if the coin has natural or artificial brilliance or lustre is to perform the “cartwheel” test.

Grasp the coin firmly between your thumb and forefinger and then slowly rotate it as you slowly tilt it to and fro. You should be able to see radiant lines of lustre as if they were spokes of light rays emanating from a wheel. If you observe this effect, then the coin most likely possesses original mint lustre. It should be full lustre, and not merely one or two rays of light. A dipped or otherwise doctored coin will not show this cartwheel effect.

Another defect to be aware of is a fingerprint on the surface. Try to steer clear of this unless you simply must have the coin and the price is reduced significantly.

A 1799 Dollar with a large fingerprintA point to remember is that no coin is perfect unless we consider the non-circulating coins produced by the various mints for sale to collectors. These are typically struck one at a time and taken from the dies by someone wearing clean cotton gloves and immediately placed into a protective holder. Here we have the ideal MS70 (or “perfect”) coin.

Coins struck for circulation can not be absolutely perfect. Due to the nature of their manufacture, circulating coins must contain one or more mint-made marks or scratches even if noticeable only with high powered magnification. These are not the defects we are speaking about. What we are saying is to avoid, at all cost, the coins containing man-made defects–this includes artificially toned and dipped coins. By selecting only those coins with outstanding eye appeal, your collection will be one to be proud of.

The best advice is to know your dealer. Build a numismatic relationship with one or more dealers whom you can trust implicitly. Make known your collecting and condition requirements. Then savour those relationships as you continue to add worthwhile coins to your collection.

Until next time, stay well, and enjoy your hobby.

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  1. I have a mysterious sounding 20cent piece that’s sound like no other 20 cent coin of its kind that IV ever came across n dropped when dropped on the ground make a dead this when it drops where others of its kind make a ring rather then A this can anyone tell me as to why this could be n how to find out


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