Cleaning Proof coins

[Taikonaut 50]

This is not something we should encourage but if needed when should we do it?

I have very few proofs I kept for years and all of them remain prestine. I bought some proofs from various sources lately and notice light toning. I was even told that toning on proofs from the Royal Mint occur quite frequently over time. Maybe the capsule are not very good?

I decide to carefully apply alcoholic wipe on a couple of affected proofs and rinse it under a tap then dapped dry with microfibre cloth. The tone is mostly gone and I notice no discernable effect. I was a bit taken back how easy the toning or disclouring come away.

Edited May 12, 2017 by Taikonaut

[IanB 175]

I would leave it alone. For me toning is a natural occurring effect and I rather like it. I don't think any capsule or container that we put a coin into will ever stop it, some might slow it down if they are sealed in someway such as the CGS type but in the end I reckon even they will let something through.

If your coins are toning then the likelihood is that it will come back again and at some point you may damage the coin when you wipe it.

How do you store your proofs, are they in a cupboard or safe and what is the temperature and humidity like? I would imagine changes in these and possible exposure to light would have some effect on how quickly toning occurs.

 

[Taikonaut 50]

I store my proofs in capsule and case that it came with sometimes not in very well controlled temperature and they all survived well without discolour or toning. The only discolouration proof I had was a gold Chinese Panda dated 1999 that came with it sealed plastic wrapper which developed discolouration about 15yrs ago so I opened the wrapper and soaked the coin in warm water with washing up liquid, rinsed and dried in microfibre cloth and left the coin in my Nichols coin cabinet for the last 15 years and it is still as good as new. I think discolour not unlike rust if not checked early can grow and become toning and more robust.

Edited May 12, 2017 by Taikonaut

[Stuntman 264]

Interesting stuff.  I'd probably be inclined to leave my proof coins alone, but good to hear that you've had good results with your careful cleaning.

[Taikonaut 50]

Still very curious how my older proof coins that are decades old are free from discolour/toning yet new more recent proofs suffer from it. Could it be modern mints contain contaminants in the water/chemical that "washes the coin" during production? 

I collect Japanese swords (genuine hand forged ones) when they are in fresh polish it looks like the finish in proof coins. We need to treat it by adding and removing oil daily for the first three weeks to expell moisture of water that was use with the various grades of polishing stones. If we don't do that it will allow rust to develop over short period of time.

[bagerap 706]

I was fortunate for four months to be the custodian of a Korehira Watanabe sword. A colleague was working away and had no desire to leave it in his house for that length of time. Although modern, it is a thing of incomparable beauty.

[Taikonaut 50]

Korehira Watanabe was a student of the late living national treasure smith Miyairi Akihira. He entered into a career into swordmaking following the 70s sword boom. In the annual sword contest in Japan he has won a couple of 3rd prizes over his career. It is worth noting smiths of the Miyairi school is known for producing quality traditionally made swords and the top smiths from that same school, Kawachi Kunihira and Miyiari Kei are both multiple 1st prize winners no less than 5-7 times each and no longer subject their work to judgement. Sorry for being off topic

Edited May 12, 2017 by Taikonaut

[Peckris 579]

1973 is probably the modern proof set with the worst reputation - an untoned set often sells at a premium over book price. The probable cause is the dyes in the red foam insert used that year. Those coins are largely untreatable IMO, and spectacularly ugly.

[argentumandcoins 70]

3 hours ago, Peckris said:

1973 is probably the modern proof set with the worst reputation - an untoned set often sells at a premium over book price. The probable cause is the dyes in the red foam insert used that year. Those coins are largely untreatable IMO, and spectacularly ugly.

I sold a perfect set on ebay a couple of months ago and the buyer complained that the card outer was rubbed on the edges! 

[argentumandcoins 70]

On ‎12‎/‎05‎/‎2017 at 10:40 PM, Taikonaut said:

Korehira Watanabe was a student of the late living national treasure smith Miyairi Akihira. He entered into a career into swordmaking following the 70s sword boom. In the annual sword contest in Japan he has won a couple of 3rd prizes over his career. It is worth noting smiths of the Miyairi school is known for producing quality traditionally made swords and the top smiths from that same school, Kawachi Kunihira and Miyiari Kei are both multiple 1st prize winners no less than 5-7 times each and no longer subject their work to judgement. Sorry for being off topic

Shin Gunto Katanas are my bag. Sold my collection recently and will look at starting again once I get my property purchase completed.

[Taikonaut 50]

I have a Shin Gunto katana with a silver family crest. I think I paid too much for it when I started collecting during the sword boom many years ago, don't mind letting it go.

[craigy 362]

15 hours ago, argentumandcoins said:

I sold a perfect set on ebay a couple of months ago and the buyer complained that the card outer was rubbed on the edges! 

this set is in a right state 

 

http://www.ebay.co.uk/itm/1973-Royal-Mint-Proof-6-Coin-Set-Including-EU-50p-Fifty-Pence-Coin-Ref04-/112412379449?hash=item1a2c4cc939:g:NrAAAOSw8lpZHrG2

[argentumandcoins 70]

2 hours ago, craigy said:

this set is in a right state 

 

http://www.ebay.co.uk/itm/1973-Royal-Mint-Proof-6-Coin-Set-Including-EU-50p-Fifty-Pence-Coin-Ref04-/112412379449?hash=item1a2c4cc939:g:NrAAAOSw8lpZHrG2

As Chris said, typical of 1973 sets. I bin them when I get them in that state.

[1949threepence 3,366]

6 hours ago, craigy said:

this set is in a right state 

 

http://www.ebay.co.uk/itm/1973-Royal-Mint-Proof-6-Coin-Set-Including-EU-50p-Fifty-Pence-Coin-Ref04-/112412379449?hash=item1a2c4cc939:g:NrAAAOSw8lpZHrG2

Crikey, I thought mine was bad enough, but it's a damn sight better than that one. Incidentally, proof sets are absolute sods to get a decent pic of.

 

 

[argentumandcoins 70]

That's a King compared to most Mike!

[1949threepence 3,366]

11 hours ago, argentumandcoins said:

That's a King compared to most Mike!

Thanks John. The ½ p, 1p, & 2p seem to have evenly toned a reddy purply colour, although most of the ½ p obverse is largely untouched. The 5p, 10p & 50p are still immaculate, as is the mint token.

I thought mine was typical of most, but maybe as you indicate, it's above average, which is good. I've got all of the period affected by discolouration between 1970 and 1979, with some of the bronze coins just slightly affected in most years. None are as bad as the 1973, but the 1974 and 1978 sets are both immaculate throughout. Some rainbow toning on the 1979 10p reverse. 

None of them seem to have altered much, between when I bought them in 1999, and now. 

  

[argentumandcoins 70]

It has to be the red dye on the insert to blame for the 73 coins. To find a mint set is very difficult whereas most 1970 sets are as issued. Bizarre and slightly annoying!

Edited August 6, 2017 by argentumandcoins

[Guest guest]

1979 is another problem year. Red insert again, even if it is a different shade.

[craigy 362]

3 hours ago, 1949threepence said:

Thanks John. The ½ p, 1p, & 2p seem to have evenly toned a reddy purply colour, although most of the ½ p obverse is largely untouched. The 5p, 10p & 50p are still immaculate, as is the mint token.

I thought mine was typical of most, but maybe as you indicate, it's above average, which is good. I've got all of the period affected by discolouration between 1970 and 1979, with some of the bronze coins just slightly affected in most years. None are as bad as the 1973, but the 1974 and 1978 sets are both immaculate throughout. Some rainbow toning on the 1979 10p reverse. 

None of them seem to have altered much, between when I bought them in 1999, and now. 

  

i have a set from the 70's thats got a green covering on the silver's, not sure which year, think it was 77

[1949threepence 3,366]

6 hours ago, argentumandcoins said:

It has to be the red dye on the insert to blame for the 73 coins. To find a mint set is very difficult whereas most 1970 sets are as issued. Bizarre and slightly annoying!

Yes. My 1970 last lsd set is perfect, bar what looks like a tiny carbon spot on the penny obverse. 

4 hours ago, Guest guest said:

1979 is another problem year. Red insert again, even if it is a different shade.

Indeed so.

3 hours ago, craigy said:

i have a set from the 70's thats got a green covering on the silver's, not sure which year, think it was 77

Do you have a pic? Be interesting to see it. 

Edited August 6, 2017 by 1949threepence

[magp 0]

I learnt the hard way (by using it all over my Henry VIII £5) that even fresh blu tac scratches coins. Pity since it really did lift the tarnish (or whatever) off.

[VickySilver 775]

When actual oxidation sets in, copper nickel is VERY hard to "adjust" with cleaning. I have a very valuable half crown that has what appears to be a couple of spots that look to be secondary to fingerprints many years ago. Previously I had some luck (and even a little on this one) by diluting ammonia 1:1 with water and lightly tamping the surface with softened/soaked cotton buds. 

Very problematic