Author Topic: Double die Mexican 500 pesos 1988.  (Read 2462 times)

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Offline $and€r

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Double die Mexican 500 pesos 1988.
« on: October 24, 2010, 12:09:11 PM »
Found this morning.. Good visible by the word "estados" ..   
World-coin collector by date and variations..

Online Figleaf

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Re: Double die Mexican 500 pesos 1988.
« Reply #1 on: October 24, 2010, 08:07:58 PM »
Eagle-eyed, Sander. You are quite right. Yet, this remains a puzzle.

Normally a machine-made double strike (it's different for hammered coins) occurs only because of the "echo-effect". This happens when there is an imbalance between the weight of the strike (the force with which the dies come down on the flan) and the hardness of the metal. Imagine the die striking the flan and meeting so much resistance that the force of the strike reverberates through the flan, turns right back and forces the die up again, before the full force of the strike is absorbed.

The experience the echo effect, strike an anvil with a hammer. If you strike hard enough, the hammer will go up again and the shakies will dance through your arm

If that happens, you would expect that the whole design would have been double-struck. Yet the snake seems quite sharp. Very mysterious.

Peter
An unidentified coin is a piece of metal. An identified coin is a piece of history.

Offline $and€r

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Re: Double die Mexican 500 pesos 1988.
« Reply #2 on: October 27, 2010, 12:05:01 PM »


If that happens, you would expect that the whole design would have been double-struck. Yet the snake seems quite sharp. Very mysterious.

Peter

I made a close up of the snake, now it's visible unsharp. I made also a photo of a "good" one and insert that into the imagine.
World-coin collector by date and variations..

Online Figleaf

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Re: Double die Mexican 500 pesos 1988.
« Reply #3 on: October 27, 2010, 04:18:47 PM »
Thanks, Sander. That helps. I see some doubling in te cactus fruit now also. I am beginning to suspect that this may have been a question of a loose lower die. That might explain why only the West by North-West part of the coin seems affected: the die, rather than the coin moved in response to the forces of the strike. Interesting.

Peter
An unidentified coin is a piece of metal. An identified coin is a piece of history.