Coated diamond?

[Racha]

I have a gemstone that tests as diamond, weights like a diamond but under magnification looks… different. Was pulling a piece of fuzz from under a prong and the surface scratched. I know stones can be diamond coated. I know diamonds can be coated to improve them visually. How can I determine or verify this is a diamond? Per friends request, I removed it from the setting to weight and heat it. There are now some clear spots in the coating.I would like to know how to remove this coating.

 

[lovedogs]

Has it been put in an ultrasonic?

 

[Garry H (Cut Nut)]

Appears to be burnt?
Get it to an appraiser.
If burnt it needs repolishing with typically almost no weight loss.

When jewelers work on a set diamond and have to heat it for soldering with a hot flame, they need to coat it in a borax flux that stops air getting to a red hot diamond.
No flux and the surface burns and looks like this photo.
Sometimes you can scratch the surface with steel and make a mark that looks like it has rubbed off - but more likely there is a line of steel particles.

 

[Racha]

Has it been put in an ultrasonic?

No.

 

[Racha]

Appears to be burnt?
Get it to an appraiser.
If burnt it needs repolishing with typically almost no weight loss.

When jewelers work on a set diamond and have to heat it for soldering with a hot flame, they need to coat it in a borax flux that stops air getting to a red hot diamond.
No flux and the surface burns and looks like this photo.
Sometimes you can scratch the surface with steel and make a mark that looks like it has rubbed off - but more likely there is a line of steel particles.

The stone appeared clear at first but something didn’t quite look right with a couple inclusions. That’s when it appeared to scratch with tweezers. I removed it from the setting, coated the stone to prevent burning with borax mixture prior to heating but even after a very short time it hazed over and that haze now seems permanent. I have worked on diamond jewelry many times but have never encountered this. It has also been soaked in acid but the haze will not go away. Is there any way to identify the coating and remove it?

 

[Garry H (Cut Nut)]

The stone appeared clear at first but something didn’t quite look right with a couple inclusions. That’s when it appeared to scratch with tweezers. I removed it from the setting, coated the stone to prevent burning with borax mixture prior to heating but even after a very short time it hazed over and that haze now seems permanent. I have worked on diamond jewelry many times but have never encountered this. It has also been soaked in acid but the haze will not go away. Is there any way to identify the coating and remove it?

Please use an appraiser. It probably needs a complete faucet touch up.