Author Topic: Off metal strike?  (Read 1602 times)

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Offline andyg

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Off metal strike?
« on: November 12, 2016, 10:33:16 PM »
These two are quite odd - they both turned up together...
The Sri Lanka 50 cents is missing it's security edge and both I think are the wrong weight at 4.6g - does anyone have the correct weights for these types?

Any ideas how to test to see if they are indeed brass and not copper-nickel?
always willing to trade modern UK coins for modern coins from elsewhere....

Offline FosseWay

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Re: Off metal strike?
« Reply #1 on: November 13, 2016, 08:52:40 AM »
My example of the Sri Lanka 50c is 21.4 mm and 5.65 g.

I am lacking the information for Tanzania (I have the coin but the info is missing in Excel  ::)) but according to Numismaster the Cu-Ni version (up to 1984) is 21 mm and 4.0 g, and the nickel-plated steel version is 19.2 mm and also 4.0 g. What date is yours?

Offline Figleaf

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Re: Off metal strike?
« Reply #2 on: November 13, 2016, 10:07:06 AM »
Tanzania 50 senti was struck 1966-1984 (Cu-Ni) and 1988-1990 (Ni clad Fe): 21 mm., 4 grams.
Sri Lanka 50 cents was struck 1972-1994 (Cu-Ni), 1996-2004 (Ni clad Fe), both 21.5 mm, 5.5 grams.

It would be interesting to know if they were struck in the same mint.

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

Offline eurocoin

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Re: Off metal strike?
« Reply #3 on: November 13, 2016, 10:11:08 AM »
What is the date on the Tanzanian coin?

The coin from Sri Lanka was minted at the British Royal Mint. The Tanzanian coin was minted at British Royal Mint and at the Birmingham Mint.

Offline andyg

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Re: Off metal strike?
« Reply #4 on: November 13, 2016, 01:13:14 PM »
Sorry Tanzania is 1973 - both I suspect are Royal Mint coins?
always willing to trade modern UK coins for modern coins from elsewhere....

Offline eurocoin

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Re: Off metal strike?
« Reply #5 on: November 13, 2016, 01:53:40 PM »
You can send them off to the Royal Mint Museum where they will be examined. After some months they will be returned to you along with a letter with their findings. That will also increase the value of the pieces (if found to be genuine).

Offline Figleaf

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Re: Off metal strike?
« Reply #6 on: November 13, 2016, 02:42:19 PM »
In spite of the similarities in mint, date and size, I would have been encouraged if it had been just one coin. It is easy to assume a wrong planchet in a press. For two different coins you need to assume wrong dies or planchets in a press twice and both results ending up in the same hands of a person who didn't have a clue. Still, hoping for a good outcome.

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

Offline eurocoin

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Re: Off metal strike?
« Reply #7 on: November 13, 2016, 03:18:57 PM »
In spite of the similarities in mint, date and size, I would have been encouraged if it had been just one coin. It is easy to assume a wrong planchet in a press. For two different coins you need to assume wrong dies or planchets in a press twice and both results ending up in the same hands of a person who didn't have a clue. Still, hoping for a good outcome.

I don't think it is that unlikely at all. It is well possible that these 2 coins were produced at the same time at the Royal Mint. Maybe someone fed machines with a wrong batch of blanks. The Royal Mint -in contrary to other mints- never waffles any production (quality) errors and just sells the coins to scrap metal dealers. So it is certainly possible that these 2 were part of a much larger batch of error coins.

Some time ago I stumbled across the following lot of coins from Bahrain, Kuwait and Haiti at a Dutch scrap metal dealer. It originated from The Royal Mint and contained many planchets and error coins:






Offline Figleaf

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Re: Off metal strike?
« Reply #8 on: November 13, 2016, 08:58:04 PM »
A scrap metal dealer sounds like a good explanation, but wouldn't you have expected a basic sense of security and quality from the UK mint and if not, why don't we see this sort of discoveries happening more often? Then again, your experience shows that such scrap metal dealers are apparently unaware of the significance of mint errors and security in a scrap yard must be close to insignificant...  Amazing :o

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

Offline andyg

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Re: Off metal strike?
« Reply #9 on: November 13, 2016, 09:33:48 PM »
My example of the Sri Lanka 50c is 21.4 mm and 5.65 g.

I am lacking the information for Tanzania (I have the coin but the info is missing in Excel  ::)) but according to Numismaster the Cu-Ni version (up to 1984) is 21 mm and 4.0 g, and the nickel-plated steel version is 19.2 mm and also 4.0 g. What date is yours?

Ta - these are definitely wrong then.

As to how these ended up in some junk - where I got them from it's quite possible that they were stripped from some collection and put with the scrap.
always willing to trade modern UK coins for modern coins from elsewhere....

Offline Globetrotter

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Re: Off metal strike?
« Reply #10 on: November 14, 2016, 09:40:11 PM »
Sri Lanka: 5.34 grs, 21.47 mm diameter, 1.97 thickness

Ole
Ole

If you're interested in coin variants please find some English documentation here:
https://sites.google.com/site/coinvarietiescollection/home
and in French on Michel's site (the presentations are not the same):
http://monnaiesetvarietes.esy.es/