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Silverlocks

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Posts posted by Silverlocks


  1. 1 hour ago, VickySilver said:

    I rather like gold and some good results on proofs with their obnoxious red spotting on some with copper alloys....

    The red spots are gold oxide formed through (I think) electrolytic reactions involving impurities on the surface of the gold.  They decompose at 160°C.  If you hunt around on the interwebs you can see videos showing you how to gently heat a coin up with a blowtorch and get rid of them.  I did try this with a sov that had a red spot and it does work.  Just don't overheat the coin.

    I used a butane torch of the sort you can buy off Amazon for melting the sugar on creme brulee (should cost about £20 including a few cans of butane), and a jeweller's charcoal soldering block to put the coin on; you can get these off ebay for about 10 quid.


  2.  

    On 3/26/2023 at 5:18 PM, VickySilver said:

    Yes, good show and please do report on results. I recently went to first ammonia and then to the reduction method on a Liberia 1965 30 dollar proof coin with great results...

    Please do rinse the funk of liberally...

    Next time I get a really grubby sov in I'll take some before and after shots.


  3. On 3/22/2023 at 10:34 PM, VickySilver said:

    My favorite solvent, and not just for organics, is the aforementioned ammonia which should be without colorizers or additives if possible. I then do soaks for varying period and use the soaked cotton buds to again work the surfaces in like manner to the acetone. This will reduce some oxidants and not damage the metal on silver, gold or copper nickel but can not guarantee copper and would therefore probably not use it on copper...

    I just bought some ammonia from a chemical supply place.  The bottle I got was really a bit too strong so I dilute it down with maybe 2-3ml ammonia to 10ml distilled water and that works fine.  It won't react with gold or silver - really the only strike against it is that the concentrated solution is very smelly.


  4. On 3/22/2023 at 11:27 AM, DrLarry said:

    I am sure this has been mentioned somewhere in this thread but on the occasions when I have used acetone I have found that it leaves an unpleasant iridescence as a residue on bronze and copper.  Similar to the fake toning discussed on other threads.  just my own experiences.  

    If you've got a nice shiny new coin you can get a film of gunge left as it evaporates off.  Rinsing the coin in distilled water and leaving it to dry on a clean cloth or some such mitigates this at the expense of it taking longer to dry.  You can get 5l bottles of distilled water off ebay for a few quid. 


  5. 6 hours ago, secret santa said:

    I had a half litre of acetone delivered successfully a year or two ago from Ebay.

    Pretty much everything I've bought I got through Ebay.  They won't ship some stuff - you can buy 32% hydrochloric acid (cleans lime-based mortar stains off brickwork) from Homebase but nobody will ship that from Ebay.  Some chemicals (e.g. Nitric acid) are subject to legal restrictions as precursors to manufacturing things like explosives or narcotics, and you can't get those without a licence, but a pretty wide variety of chemicals are available on the open market and can be ordered and shipped.

    In theory, you could do precious metal recovery with chemicals that can be obtained without a licence and mostly purchased online.  Given the fumes, you might not want to try that in a council flat, though.


  6. On 3/22/2023 at 10:01 PM, copper123 said:

    It might not be legal to post it , being a volitile solvent and all that ....

    Vendors on Ebay will ship most chemicals that aren't subject to legal restrictions.  If they're dangerous they will come packed in a plastic bag full of activated charcoal.

    • Like 1

  7. I've tried a few solvents, notably:

    • Acetone - dissolves most grease based gunge.  It's also miscable with water so you can rinse coins in distilled water if desired.
    • Isopropyl Alcohol - Acetone is better, IMO, but this works.
    • Limonene - This is degreasing agent widely used in cleaning electronics.  It's the orange smelling stuff you use to clean heatsink gunk off CPUs, for those familiar with it.  It works, but it's very, very smelly and has no discernible advantages over acetone.
    • Ammonia solution - Probably the strongest cleaning agent for grease based stains; you can rinse coins off with distilled water.  It won't react with silver or gold, but it will form cuprammonium complexes from copper salts.  I've never tried it with copper coins.

    I got a little borosilicate petri dish and lid off Ebay.  This lets you immerse a coin with about 10ml of solvent and pop the lid on it (good for anything that produces fumes).  I also got a 10ml pipette for transfering solvents into the dish.  Usually soaking in acetone and/or ammonia solution for a few minutes is enough to dislodge most gunge and bring the coin up nicely.

    One thing I did consider is getting a water pik toothbrush for rinsing and using distilled water for the rinse.

     


  8. 7 minutes ago, Peckris 2 said:

    It is indeed - and they're still functioning, though it seems to be mostly gold these days, a long long way from the 'good old days' of R&L! (whose Blackpool shop I actually went to in  the late 70s and bought a few things from...)

    I wondered about that - Lawrence Chard is fairly active on social media these days, which is where I heard of Chards from.  You can see him pop up in The Silver Forum from time to time and they put out a bit of content on YT.


  9. On 1/8/2023 at 11:15 AM, blakeyboy said:

    With the reduction in birthrates,   there is now one born every 96 seconds...

     

    Never underestimate how stupid people can be, and how led-by-the-nose.

    Last month my old mate asked me why he saw so many stupid people about.

    I pointed out that, all things being even, ignoring things like the  'brain 'drain' to the cities, the IQ distribution curve

    is centred on 100, and for every person he knew whose IQ is 120, he will meet one whose IQ is 80.

    So, for the ten or so of us in this thread, there are ten people, also into coins, who are finding the RM coins appealing.....

    There's a saying that goes:

    Think how dumb the average person is.

    Now, remember, half the people are dumber than that.

    • Like 1

  10. 11 hours ago, Coinery said:

    Wow, temperature, that’s interesting. I always had it in my mind a damper atmosphere would work better…I guess that’s from thinking of other metals oxidising more in those conditions?

    Really appreciate your comments, very interesting! 👍

    As a general rule of thumb, rate of reaction doubles for about every 10°C temperature.

    • Like 2

  11. The nice thing about George V sovs is that you can get really good examples at bullion prices.  Something like 440 million were minted in total and they were uncirculated for most of the 22 years they were in production.  Most of mine would grade between AU-58 and MS-63 and I've got a 1918 that would probably do better than that.  They're nice coins but Georges in that condition are fairly common and they're not worth grading.

    I know folks who love their premium slabbed coins and actually buy proof sets from the RM to send off to NGC in pursuit of the coveted PF70 Ultra Cameo.  However, I can't really bring myself to get excited about slabbed coins, let alone paying top dollar for them.

    One can see the point in the US with the enormous trade in restoring Morgan dollars and suchlike.  Having an expert certify that the thing is at least genuine, especially when you're going to shell out hundreds of dollars for a coin with a melt value of $20, sort of makes sense.  Buying a brand new proof coin and immediately bundling it off to a grading firm - not so much.  

    • Like 2
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