Diamond suppliers often "bake" stones. This causes them to expel yellow-causing nitrogen and become white, but also makes them more brittle. A baked diamond can often be recognized by its unnatural pasty white color.

Is there any scientific or chemical way to detect that a diamond has been heat treated?

  • 1
    $\begingroup$ Quote from link "Baked diamonds, or annealed diamonds as some people refer to them, though they are undetectable to labs or independent appraisers have one major flaw, they are brittle!" diamondcuttersintl.com/monarch-diamond // So it doesn't seem like the standard gemological equipment can detect such a treated diamond. The website refers to such treated diamonds as causing an industry crisis. $\endgroup$
    – MaxW
    Commented Dec 22, 2015 at 17:59
  • 1
    $\begingroup$ This really intrigues me. // A "pasty white color" would be due to internal cracks which would reflect/refract light in odd ways. // I'd expect that such a treated diamond wouldn't break by cleaving along a single plane in the crystal, but shatter. // It wouldn't seem that the somewhat exotic technique of thermoluminescence would help. It would be one shot, but you could reenergize the diamond using UV light or x-rays. $\endgroup$
    – MaxW
    Commented Dec 23, 2015 at 2:30
  • $\begingroup$ A change in properties means a change in structure, therefore it seems that X-Ray diffractography should be able to tell the difference. $\endgroup$
    – A.K.
    Commented Dec 23, 2015 at 3:58
  • $\begingroup$ @A.K. Maybe it's just not accurate enough to detect the difference though. $\endgroup$ Commented Jan 4, 2016 at 12:56


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.