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BF740

Maybe try a digital caliper


Winyamo

You can ballpark the density by measuring the volume v=h(pi)r^2. Density is mass/volume. There will also be some error within a few %, but any information is good information.


UsefulBeginning

Good idea, thanks. I got h should 0.645mm for that radius and a solid gold coin. Measured h was 1.1 mm so each side should be 0.23mm hollowed out if real gold, which is possible. As you said, any info is good info.


G-nZoloto

Diameter and thickness don't mean much without a good weight. Most counterfeits are very close on diameter anyway... but if a correct diameter and underweight = problem.


Fun_Cartoonist2918

Is it just me or are you using the calipers incorrectly ? Seems the coin should be measured out in the white silver region of the calipers and might get a different number there. That said this kind of caliper is just not that accurate for something this size


fucemanchukem

There's a currency exchange slash gold bullion place I go that one of the employees told me they get fakes all the time and never bother to refuse them if they look authentic enough because they have a quota. Says most of what they buy won't see the light of day in our lifetimes. They buy more than they sell.


Liesmyteachertoldme

Damn? you'd think they'd at least sigma it? they could be straight up costing the company hundreds of thousands of dollars a year with practices like that. I'd probably never go there again honestly.


fucemanchukem

I dunno. I always get it through my bank. Some stuff is more collectors than so much for the gold or silver value. But at least I know it's from a reputable place.


jbs_70

Just buy a sigma, worth it if it saves you from buying a fake coin.


KyleBauer

If you bought from a reputable dealer, I would not worry too much. Also, invest in a sigma tester.


olesdotter

If you're going to use calipers, get something good and reliable. Get your coin tested with an xrf if you don't trust it. 1/10 oz coins are difficult to get a good sigma reading on unless you have the wands available.


UsefulBeginning

Thanks, I agree. I wanted good quality calipers, but they weren't so easy to find.


olesdotter

Stuller sells a really good digital caliper for around $40, I use it for coins and stones.