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Specific gravity test - there are enough demos on YouTube

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On 7/23/2020 at 9:06 PM, Diaconis said:

Specific gravity test - there are enough demos on YouTube

But if the weight and dimensions are correct, it must be made from the correct metal composition.  It does look cast though.

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1 hour ago, Nick said:

But if the weight and dimensions are correct, it must be made from the correct metal composition.  It does look cast though.

If it was a polished disk then I agree, but the overall dimensions do not take into account any variances in reeding/relief/embossing. The volume of displaced water accounts for this.

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I am not particularly concerned about SG on this coin as IMO it fails on other merits. I think it might actually be die struck but the counterfeit dies created by something similar to spark discharge - might be possible by computer guided laser?? 

There are many other details that are all wrong that I left out. If you enlarge the photo at all, you can see the roughness to the fields and devices and as mentioned the loss of critical detail in many areas....

In any case, although I love my Gothic florins would sadly have to reject this one. I was trying to be polite, so please excuse if I am not quite so.

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3 hours ago, Diaconis said:

If it was a polished disk then I agree, but the overall dimensions do not take into account any variances in reeding/relief/embossing. The volume of displaced water accounts for this.

You'd have to have really quite precise equipment to distinguish between minor differences in volume. Callipers may be quicker ! 

 

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I would balance the coin on a finger and gently tap with another coin to see if it rings like silver. The sound of silver is very distinctive. cupronickel gives a dull short ring. 

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1 hour ago, Sword said:

I would balance the coin on a finger and gently tap with another coin to see if it rings like silver. The sound of silver is very distinctive. cupronickel gives a dull short ring. 

Best is to compare with another florin of known composition.

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Although good practice to calculate SG (and a minor pain in the ass). This coin fails on more important grounds, including those I have broached.

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If it has the right dimension and weight, then calculating SG is pointless- it will also seem correct.

What is important is knowing about other silver -looking alloys that have the same SG as .925...

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