Moissanite Coated With Diamond Film Spotted by Lab

Moderators: PinkDiamond, John

Post Reply
User avatar
PinkDiamond
Posts: 15409
Joined: Thu Jun 04, 2015 9:30 pm
Location: Ozark Mountains

Moissanite Coated With Diamond Film Spotted by Lab

Post by PinkDiamond »

Whoa, a coating that thin registered as diamond? This is definitely going to be a problem for the industry. :?

Moissanite Coated With Diamond Film Spotted by Lab
March 21, 2019 by Rob Bates

Image

"A Russian gem lab recently spotted a rough synthetic moissanite coated with a thin diamond film (pictured) and warned that coated simulants could prove “challenging to identify,” according to an article in the winter 2018 edition of the Gemological Institute of America publication Gems & Gemology.

The 5.35 ct. crystal’s “luster and thermal properties correspond[ed] to diamond,” said the note, credited to researchers at the Far East Geological Institute in Vladivostok, Russia. “Even with a very thin coating that did not exceed 0.001 mm., the sample tested positive for diamond.”

It warned that an “application of thin diamond films onto non-diamond material could be an issue for gemologists in the future.”

The transparent yellow octahedron was submitted as a rough diamond to the Far East Geological Institute, the note said.

Its face “showed a stepped appearance, and the edges had parallel grooves and combinational surfaces,” the story reported. “The faces and edges were smooth except for one face where mechanical damage was noticeable.”

But while tests for thermal conductivity indicated the stone was a diamond, tests for electrical conductivity, commonly used to identify synthetic moissanite, weren’t as conclusive: Some areas of the stone, primarily its edges, indicated it was a diamond, but its smooth face and dimples pointed to synthetic moissanite.

A look at the stone through a gemological microscope revealed it had no inclusions typically associated with natural diamonds. Instead, it contained only small, parallel needlelike inclusions, a characteristic of synthetic moissanite.

Image
The 5.35 ct. rough crystal evidenced needlelike inclusions, which are characteristic of synthetic moissanite and not a natural diamond.

The full note can be seen here. ... "

https://www.jckonline.com/editorial-art ... -334329457
PinkDiamond
ISG Registered Gemologist


· ´¨¨)) -:¦:-¸.·´ .·´¨¨))
((¸¸.·´ ..·´ There are miracles left for you to do .... -:¦:- -:¦:-
-:¦:- ((¸¸.·´* It all begins inside of you. ;)
User avatar
rocks2dust
Posts: 742
Joined: Thu Jun 11, 2015 5:41 pm
Location: Oregon
Contact:

Re: Moissanite Coated With Diamond Film Spotted by Lab

Post by rocks2dust »

Interesting. Probably easily done using the same equipment used to make CVD synthetic diamonds. Shorter time, since they don't have to grow an entire crystal from scratch and they could pump out more of these.

I can hear the rationalizations already: "Well, it IS diamond after all, same as a cultured pearl."
r2d

surplus odds and ends that I have on ebid.net
· Xtra gemstones
· Xcess fossils, minerals and rough
· Everything else
Post Reply