Catalogus van Belgische Numismatische Uitgiften

Munten Overige ~ Pieces Autre ~ Coins Other => Vervalsingen ~ Fausses ~ Forgeries => Topic gestart door: jagoedo op maart 20, 2015, 10:01:31 am

Titel: Vervalsingen - interessante info
Bericht door: jagoedo op maart 20, 2015, 10:01:31 am
Tijdens het lezen op coincommunity.com dit interessant stukje tegengekomen door gebruiker Swamperbob.
Link http://www.coincommunity.com/forum/topic.asp?TOPIC_ID=193220

Citaat
The forgeries of this Russian coin have been around a long time - from the 60s at least. As noted in the files you listed the 1 Ruble is the most common forgery of the type.

You have the correct weight now given in the Sixbid auction - 5.56 grams. Any deviation of 1/10th gram would be a bad indication. Of course this coin may not have had a high level of accuracy because it is copper - but a tiny coin requires a rather precise thickness to get a full strike so I would not expect a large variation in thickness at all.

A split top and split tail reed is created when a forgery is pressed through a tapered ring die that cuts the reeds into the edge by gradually scraping off some of the edge and curling it up to form the reeds. If you have ever used a manual pipe threader the principle is the same. This process usually involves a stack of coins to keep the reeds perpendicular to the faces. The following is a sketch of the ring die.

Afbeelding 1

Citaat
The result of this process is a small closed seam along the top of each reed and a split at each end. The sketch below shows the results with the traces marked in red.

Afbeelding 2

Citaat
One of the ways to conceal the split ends is to grind one or both corners and the top of the reeds. Here is a sketch of what I mean by the clue left at the corner by grinding. It seems quite clear to me that is rounded corner is what your coin has. A collar struck coin in high grade usually does not have corners as rounded or irregular as what I see here.

Afbeelding 3

Citaat
As I noted above most forgers press a stack of coins at one time to keep the coins from turning in the die. Too small a stack of coins and they can tilt resulting in slanted reeds. The following is a picture of an 1878 Trade dollar forgery with tilted reeds. This tilt will ONLY OCCUR on a short segment of the circumference, but it can not be seen on a normal collar that rises vertically aligned by the die press itself.

Afbeelding 4

Citaat
On your coin if you look at the center of the bottom edge picture you will see reeds that are NOT perpendicular to the faces.

I would, based on the reeds, call this coin a numismatic forgery.
Titel: Re: Vervalsingen - interessante info
Bericht door: Aernout op maart 21, 2015, 13:57:28 pm
Leuk om te lezen.

Afbeelding 3 en 4 zijn hetzelfde  :-\

mvg,
Aernout
Titel: Re: Vervalsingen - interessante info
Bericht door: Atlantic op maart 21, 2015, 17:05:21 pm
Straf, interessant om te lezen!
Titel: Re: Vervalsingen - interessante info
Bericht door: jagoedo op maart 26, 2015, 13:16:37 pm
Heb het aangepast en ook een link toegevoegd.
Titel: Re: Vervalsingen - interessante info
Bericht door: Aernout op maart 26, 2015, 18:24:49 pm
Met dank  :D

mvg,
Aernout