Some buyers asked me to look for CVD melee, but I found its price is super expensive than HPHT melee.
BTW, only some suppliers has that, even I finally found that, but still confused.
Both lab grown, why their price are so different? Any ideas?
CVD, chemical vapor deposition and HPHT, high pressure high temperature melees have slightly different properties.
CVD often offers higher clarity, but can have a tint to them
HPHT, have greater structural integrity but are more prone to inclusions and such.
This is at least how I understand the processes.
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Yggdrasil is correct, but even though both are lab-grown diamonds, HPHT is the most efficient method for producing small melee stones, so it’s cheaper. CVD melee diamonds are produced in smaller quantities and are sometimes specifically requested by buyers, which pushes the price higher. The price gap isn’t because one is “better”; it’s purely about which method is economically sensible for tiny stones. Once you explain it this way to your clients, they usually get it and switch to HPHT for melee accents. Others may have a different opinion.
Regards,
~AJ
Hello,
If memory serves, it is less expensive to produce lab grown melee via HPHT than CVD…so most lab melees are HPHT.
most larger stones are CVD
one difference between the two types is that some HPHT diamonds exhibit temporary phosphorescence (ie: glows in the dark…ie: dim restaurant) after exposure to certain light sources (ie: incandescent, sunlight)
this could be an important consideration when combining a CVD center stone with HPHT melee
or, mixing HPHT and CVD melee (and or natural diamonds) in a setting…or in melee inventory
this can be “checked” by using a UV flashlight
https://www.gia.edu/gems-gemology/spring-2023-gemnews-hpht-diamond-phosphorescence
this is a great video on lab grown diamonds…in depth yet not overly technical…gives a thorough explanation on each process, how the processes affect the grow and final output…the characteristics of each…the differences… i watched it 3 times!
julie
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You are right. I discussed with my buyer, he said HPHT melee is Type II, but CVD melee is Type II A. Some luxury jewelry use CVD melee with natural diamonds as accent stones, when test the diamonds using pen tester, some HPHT will show fake diamonds, but CVD always(99%) show natural.
Yes, HPHT sometimes has inclusions inside, and CVD rare has. But as melee, no one will check the purity of accent diamonds. My client tell me that CVD melee could have big possibility to pass the pen tester.
yes, most of my clients don’t care HPHT or CVD, they only care the price. But one of my client said, CVD melee has big possibility to pass the pen tester, HPHT no