Dirt on uncirculated coins

tjkillian

I was talking with someone at the Long Beach show and he said that all uncirculated coins from the 19th century have had their dirt removed. He basically said that any coin that was kept in a well-preserved enviroment would naturally get dirt on them as dust/dirt is in the air. So assume that a nice Seated Liberty Quarter was well-kept in a nice coin cabinet, drawers opened slowly to minimize cabinet friction. Since the cabinet would not be air-tite, dust would gather on the coin. Fast forward to the late 20th or early 21st century, a dealer gets a hold a such a coin, he/she would naturally remove any dirt on it, probably chemically, say acetone or distilled water, at the very least.

Now, suppose you have a coin from the 19th century, in a PCGS holder that has a fair amount of dirt on it. Could that be an indication that the coin has never been dipped, cleaned or improved in any way? Another words, is the presents of small amount of dirt in the nooks and crannies of a coin and indication of originality?

Tom

Steve27

I find your definition of "dirt" to be ridiculous. Dirt is synonymous with soil in my mind, and as for dust, according to studies, the major component of dust is dead skin cells. Thus, I think your Long Beach friend is full of it (just don't ask what "it" is).

Shamika

Tom,

Are you refering to an instance as seen on the reverse of THIS PCGS MS63 LARGE CENT?

Derek2100

Why would you want dirt on a coin anyhow?

cladking

Dust is usually less than 15% protein though it is said to be higher in Hawaii. Most
of this protein is probably mites and various other dead insects. Dust will vary depend-
ing on numerous factors but I seriously doubt that under normal conditions that any at
all would adhere to coins in a collection. Smoke and other particulate or high moisture
"dirt" might stick but not dust.

Coins that are exposed to the conditions which cause dirt accumulation will acquire it
very readily and would be easily duplicated.