OK, so this might look totally off-topic, right?
But, is it really? Chemistry plays a big part in our hobby, whether we acknowledge it or not. The composition of our coins, obviously... But also the gasses we store them in, the plastics we wrap around both, and of course the contaminants and the damage they do.
Not that I'm suggesting we all rush off to http://www.fieldtestedsystems.com/ and buy ourselves a bunch of lab gear, but a little knowledge can be valuable, no? And the price is right... :angel:
(http://www.fieldtestedsystems.com/download/PeriodicTableOfSpectra.png)
This is closer to what goes on where i work than i ever expected to see on this forum... haha.
Quote from: 'LooseChange' pid='89557' dateline='1464478251'This is closer to what goes on where i work than i ever expected to see on this forum... haha.
Heh, and looks very similar to what goes on where my daughter works. Something about DNA....Do Not Ask. Nah, just made that up, she's generally very obliging :biggrin:
The study of Metallurgy would be useful as well I imagine :good:
Quote from: 'autocoupler' pid='89558' dateline='1464490509'Quote from: 'LooseChange' pid='89557' dateline='1464478251'This is closer to what goes on where i work than i ever expected to see on this forum... haha.
she's generally very obliging :biggrin:
Really :blush2:
Quote from: 'ausjack' pid='89563' dateline='1464494771'Quote from: 'autocoupler' pid='89558' dateline='1464490509'she's generally very obliging :biggrin:
Really :blush2:
DOWN, Boy! *THWACK!* :dodgy:
:laugh2: just asking :blush2:
This particular graph will not be of much help to us as coin collectors. Those are emission lines. Metals do not emit this light until they are heated rather higher than we coin collectors typically like to heat our coins to. The ICP-OES I use at work, for example, heats the sample up to 6000 deg C - though you do have to dissolve the sample in acid first.
More convenient (and less destructive) for coin collectors would be XRF spectra. X-ray Fluorescence does not destroy the sample being tested. They even sell little handheld XRF widgets that look like Star Trek phasor guns (but cost the price of a mid-sized car).
Quote from: 'Sapyx' pid='89589' dateline='1464506315'More convenient (and less destructive) for coin collectors would be XRF spectra.
Yes, but the spectra will still be the same, no?
And we can certainly destroy things other than the coins, such as the verdigris we scrape off for example.
I would love to destroy the verdigris (or better still remove all those extraneous atoms and reconstitute the copper) without damaging the coin. Of course any technique that might do that would probably cost several orders of magnitude more than the potential value of a "repaired" coin.
Pity; it is simple and cheap to remove sulphides (tarnish) from silver with nary a sign it was once there. Well, no sign to the naked eye in mediocre light.
Quote from: 'JeffH' pid='89594' dateline='1464509740'Of course any technique that might do that would probably cost several orders of magnitude more than the potential value of a "repaired" coin.
Yeah. And not only that, but even when, one day, we have armies of nanobots to go in and rearrange molecules one by one, someone will come up with a way to trace their activities and bodybag a coin as 'cleaned'. :(
Some days I wonder what w're really doing in this hobby, y'know... :(
Quote from: 'Fulvio' pid='89592' dateline='1464507429'Quote from: 'Sapyx' pid='89589' dateline='1464506315'More convenient (and less destructive) for coin collectors would be XRF spectra.
Yes, but the spectra will still be the same, no?
No. The spectra in the OP are emission visible-light wavelengths (300-800 nm or thereabouts). That's light that you can see, with the colours shown on the chart being the colours you would actually see with your eyes. Make sodium hot enough to glow and it glows yellow, for example - that's why sodium streetlights are yellow. XRF wavelengths are in the x-ray and extreme ultraviolet wavelength range (0.05 to 25 nm). You definitely can't see those x-rays.
XRF is a "fluorescence" technique. You don't have to make the sample hot enough to glow x-rays, you only need to shine an x-ray beam of known wavelength onto the target. The radiation fluoresces - is absorbed by the target and re-emitted at lower wavelengths - at frequencies that are distinctive for each element.
Thanks for that. In my defence, I'm a bit rusty after 40 years or so. ;)
Quote from: 'Fulvio' pid='89602' dateline='1464529080'Quote from: 'JeffH' pid='89594' dateline='1464509740'Of course any technique that might do that would probably cost several orders of magnitude more than the potential value of a "repaired" coin.
Yeah. And not only that, but even when, one day, we have armies of nanobots to go in and rearrange molecules one by one, someone will come up with a way to trace their activities and bodybag a coin as 'cleaned'. :(
Some days I wonder what w're really doing in this hobby, y'know... :(
When that day comes then the hobby will be dead. They will just rearrange the molecules to turn a washer of a coin into say a MS68 1930 English die penny.
Quote from: 'nealeffendi' pid='89677' dateline='1464654852'When that day comes then the hobby will be dead. They will just rearrange the molecules to turn a washer of a coin into say a MS68 1930 English die penny.
Absolutely, yes. And it will happen, sooner or later.
Heck, they don't even have to fiddle the coins.. just make a die that's indistinguishable from what you want to copy, and go nuts with it. You could even use it to make your very own errors, varieties, flaws and sports!
I give it 20 years, at most. :(
Daniel Carr is doing this right now with US coins.
http://www.coincommunity.com/forum/topic.asp?TOPIC_ID=260794
Quote from: 'trout' pid='89695' dateline='1464672468'Daniel Carr is doing this right now with US coins.
:dodgy::dodgy::dodgy::dodgy::dodgy::dodgy::dodgy:
Shoulda called it the '
Dodgy Brothers Mint'. ;)