Other than inscription, are lab and mined distinguishable?

[ChicagoMan]

Should a lab-grown and mined diamond not have a girdle inscription, are they distinguishable from each other?

 

[OoohShiny]

https://www.pricescope.com/community/threads/gia-on-hpht-synthetics-fall-2017.235388/

 

[ChristineRose]

The short answer is no.

They can be distinguished with special equipment that looks at the microscopic growth patterns. Synthetics have very neat growth patterns compared to natural.

Occasionally a synthetic will have unique inclusions, and often a mined stone will have inclusions which wouldn't appear in a synthetic.

Synthetics tend to be different colors, but you can't really tell whether it's an outlier or a synthetic.

All grading labs have the equipment to tell a synthetic.

 

[denverappraiser]

They usually look very similar, which is not really a surprise since they are very similar. At least half are easy because of the inclusions and similar clues (I2s are usually pretty easy for example). There are relatively common tools to separate them quickly about 98% of the time, and there are some exotic tools that can do 100% The big labs all have the high-end thing, most jewelers don’t.