ScottO Posted February 6, 2011 Report Share Posted February 6, 2011 was testing my chinese 3 cash from the northen sung (1086-1100) with a magnetic screwdriver (had to repair comp) and tested it against some more recent iron pieces (german notsgeld etc) and noticed that the german stuff stuck to the magnet, however the cash coin had very little pull whatsover (it was slight but hardly any movement towards it) and i know that magnetism fades over time, so is this a good test to do for authentic age? Quote Link to comment Share on other sites More sharing options...
thedeadpoint Posted February 6, 2011 Report Share Posted February 6, 2011 I'm guessing theres way too much variability with the methods, subject, and instrument to make that a "good test". Great thinking though. Wouldn't it be cool to have a spectrum of magnets you pass over each coin at a set height. When the coin gets attracted, then the scale tells you the age! Quote Link to comment Share on other sites More sharing options...
ccg Posted February 6, 2011 Report Share Posted February 6, 2011 I know iron is magnetic, but is iron oxide magnetic? Quote Link to comment Share on other sites More sharing options...
ScottO Posted February 6, 2011 Author Report Share Posted February 6, 2011 well i got a rusty 1918 german notsgeld piece and it stuck. i do have access to a powerful hard drive magnet, but i dont really want to use it cos.. it is powerful. Quote Link to comment Share on other sites More sharing options...
ccg Posted February 7, 2011 Report Share Posted February 7, 2011 well i got a rusty 1918 german notsgeld piece and it stuck. Yes, but it was still be mostly steel under the surface. The cash coin is likely throughly rusted. The other issue is the amount of alloy present (zinc et al.), and how that might affect the magnetic properties. Quote Link to comment Share on other sites More sharing options...
just carl Posted February 10, 2011 Report Share Posted February 10, 2011 I know iron is magnetic, but is iron oxide magnetic? Oddly enough almost anything could be made to be magnetic. And yes, even Oxides of metals stay magnetic if the original material was magnitized. And example of this is AlNiCo, which is really a powerful magnet and yet contains no Iron at all. Magnitism can spread from one substance to another also, so using a magnet on a coin is not real smart. Magnetically inducing such a polarity could create more rapid Oxidationing of your coins. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.