Diamond Tester??

[Rook]

Hello,

I was at a local mall jewelery store with my girlfriend this weekend casually looking around. My girl wanted to look at diamonds of course. But, I noticed that before they give you a diamond, and after you give it back to them, the used a little "diamond tester" on the diamond to insure it was real.

The tester was a little larger than a pen, maybe twice a wide. It had a small electrode on the end that you place up to the diamond and it sends out a small volt of electricity to the diamond. Then it tells you if the stone is real.

Well I have my doubts about the tester. Has anyone else seen these and does anyone know if they are any good, or just plan crap that the store uses for a selling device.

I am guessing a selling devise since they test it twice, one before giving it to you, and again when you give the ring back. Unless they have a large problem with people switching rings quickly in the transaction, it seems like a sales tactic.

Any thoughts.

 

[mike04456]

I doubt it's a selling tactic. There is indeed enough of a problem with thieves palming and switching diamonds that I'm not surprised some stores do this as a matter of course.

The tester they're using tests thermal inertia, that is, the degree to which the gem material conducts heat. Diamond has very high thermal conductivity, so it's an easy way to identify simulants--at least until moissanite came along. I guess they're not as concerned with people switching diamond with moissanite, since it's a lot more expensive than CZ. Most thieves and con men are cheapskates at heart and don't like spending a lot of money on a scam.

 

[DiamondOptics]

Hey Rook,


Maybe I'm wrong, but doesn't moissanite get confused for a diamond when checked by a diamond tester?

kirk

 

[DiamondOptics]

Hi Lawgem,

Both our posts came along the same time. With one word in common, "Moissanite"

Glad you brought it up...


kirk

 

[Rook]

Hmmm, Well I stand corrected. Seeing that it was at a one store in the mall, and no others, and that it was a recent addition for the store I thought it might be a tactic. Also, I have always thought that most testers were very inaccurate at best. At least the quicky ones like this store uses.

Kirk,

I have no idea, maybe Lawgem or someone else will no better. I know Moissante is very simular in composition to diamond, but I have never heard of its reaction to this type of diamond tester.

 

[mike04456]

This store, or its chain, may have experienced some thefts lately. Or they might have instituted this poliy to lower their insurance rates.

Moissanite will give a "diamond" reaction on a traditional thermal tester because its thermal inertia is close enough to diamond. There are moissanite testers, which, interestingly enough, are sold by the same company that makes moissanite. Some people believe the company is really in the business of selling testers, not gems. Someone asserted to me once that they had made more money off the testers than the stones, though I have no way of confirming that.