Gyroscopic Investing

Well I promised a review of the Fisch gold coin competitor Gold Coin Balance available here:

www.goldcoinbalance.com

I have been really busy and will do a full review. But my mini-review is it's a good deal and works. The injection molding around the dimension scales needs a little trim with a razor blade to cut off some excess to have it be a good fit. But overall this is a really handy tool and for the price is a great deal if you are buying coins from lesser known sources and want to quickly test them.

I bought mine a couple months ago and tested all my coins.  Honestly I'm not sure why anyone would buy a Fisch tester since both Gold Coin balance and the Fisch tester seem to be the pretty much the same thing.

That's an odd coincidence that you posted this review today, because I just received my Gold Coin Balance in the mail today.

I agree completely: It's a really handy tool that is a great deal for the price. I've tried it on a Krugerrand and an Eagle so far, and it works as advertised on both of them.

The device's simple, minimalist design consisting of a single rigid piece of plastic appeals to me. No moving or interlocking parts = virtually no wear and tear or risk of breaking.

FarmerD wrote: I bought mine a couple months ago and tested all my coins.  Honestly I'm not sure why anyone would buy a Fisch tester since both Gold Coin balance and the Fisch tester seem to be the pretty much the same thing.

The Fisch tester comes in a pack of 5 that does multiple coin sizes such as 1/2 ounce, 1/10 ounce and 1/4 ounce coins.

As the price of gold rises, it's entirely possible that we might be using less than 1 ounce coins in our PP. As of right now, the spread on 1 ounce gold coins is far superior to that of smaller coins.

But what if 1 ounce of gold became worth $10k? Then we'd probably be using $1k 1/10 ounce coins, assuming our salaries and investment allowances didn't also go up 500%.

The Gold Coin Balance looks like a great deal if you are just doing one-ounce bullion coins.  If you are going to venture into Sovereigns or other "off-brand" gold coins, though, you need the Fisch, as TripleB says.  Or you can go into the direct measurement mode.

I used to use old manual calipers and a triple-beam balance (lab-type stuff), but reasonably accurate digital calipers and scales are available (I got mine at Harbor Freight) for not much more than the cost of the Coin Balance.  It really is very easy to measure the appropriate parameters to see if you have a fake.  I have seen two fakes (one gold, one silver) and both were easily picked up by the scale.

All of these methods may not be able to detect tungsten fakes, though.  For information about the "ring test" see here:http://gyroscopicinvesting.com/forum/ht ... ic.php?t=8

The "ring test" does seem to work, and the Audacity software is pretty easy to use.  I've been playing around with another ring test method using things you have lying around the house.  If you carefully balance the coin to be tested on the tip of your index finger and gently (emphasis on gently) strike the edge of the coin to be tested with the edge of another coin you get a most pleasing (and characteristic) ring.  Coins of a given type have a surprisingly consistent ring, and the human ear is usually pretty good at detecting that consistency.

Another tungsten detection method I've considered (but not tried) is taking advantage of the different thermal properties of gold and tungsten.  Gold conducts heat much better than tungsten, so theoretically if you were to dip a gold coin and a tungsten fake in hot water at the same time the gold coin would get warmer faster, and your finger detectors should be able to differentiate the two.

Or just buy the Gold Coin Balance

I bought a Gold Coin Balance and it arrived broken in half. I mailed the broken balance back to the vendor with an explanation and received 2 new balances in the mail at no cost. I took one of the balances to my box at the bank and it worked on all the 1 oz coins in my collection.

Everyone who buys coins should have one of these balances in their pocket when they shop. Using it not only protects the individual buyer, it also sends the right message to sellers.

This is a really nice deal.

The only thing that keeps me from feeling like I completely wasted my money on my Fisch testers is the ability to test fractional PMs, which lately has been the majority of my purchases.

I strongly recommend folks who buy PMs get one of these as you really can't beat the price.

A question I have, is whether either the Fisch or Gold Coin Balance can detect a tungsten alloy fake. I've heard tungsten has a density very close to Gold, so how will I know that the balances are correctly tuned to the exact weight of a 1-ounce gold coin if I don't have a fake to try it on?

Does anyone have audio mapping of a tungsten fake?

Khisanth wrote:I've heard tungsten has a density very close to Gold

It does, but it is apparently relatively difficult to strike into coins (much easier to make fake "gold" bars with tungsten).

Gold and sliver are diamagnetic (oppose a strong magnetic field) while tungsten is paramagnetic (slightly attracted to a strong magnetic field).  And I'm rapidly approaching my limits of physics and chemistry knowledge.

I don't have a tungsten fake, but there are a number of YouTube videos showing the behavior of various real and fake coins versus neodymium (rare earth) magnets.  I don't know how reliable such tests are, but they appear promising.

Looks like a small rare-earth magnet is another tool in the arsenal of fake-coin detection.  Worst case you can use it to detect old-style magnetic fakes.

Khisanth wrote: A question I have, is whether either the Fisch or Gold Coin Balance can detect a tungsten alloy fake. I've heard tungsten has a density very close to Gold, so how will I know that the balances are correctly tuned to the exact weight of a 1-ounce gold coin if I don't have a fake to try it on?

Does anyone have audio mapping of a tungsten fake?

If you can make a tungsten coin that tricks the balance, the makers of this particular balance will pay you the spot price of gold.

I just bought a little spectral app for my iPhone "SigScope".  You can set the phone on the table and it gives you a real time spectral signature from the audio input.  If you drop a coin nearby you can see immediately see the spectral response.  (Usually 3 well defined peaks).  The signature is unique for each coin type.  It's very quick and easy to test a coin - and I don't know how you would be able to fool it.

Mark Leavy wrote: I just bought a little spectral app for my iPhone "SigScope".  You can set the phone on the table and it gives you a real time spectral signature from the audio input.  If you drop a coin nearby you can see immediately see the spectral response.  (Usually 3 well defined peaks).  The signature is unique for each coin type.   It's very quick and easy to test a coin - and I don't know how you would be able to fool it.

That sounds really cool.  This would be good for the mixed alloy coins like Eagles and Krugerrands, but I'm not sure I'd drop my Maple Leafs on the table.  Gotta keep those babies in mint condition...I even avoid putting fingerprints on the face of the coin.

Ordered one today, and gave Craig props in the special order instructions section.

Got mine in the mail the other day. I don't have any fakes to try it out on, but the krugs do fit snugly.

I bought a gold coin balance, but on reflection I thought I could have spent my money more wisely on a similar priced kit that I could test all my coins with. I got a good kit from http://www.silver-dollar.co.uk/silvertest

They also supply a good testing magnet, which is very good for tsting silver coins.