HCA is only used as a diamond rejection tool, not selection tool. Some jeweller will tell you it is not relevant anymore, but then, I will still use it as rejection tool. The reason why it cannot be used as selection is that it only take into account 17 facets out of 57 facets, according to: http://www.goodoldgold.com/consumers-guide-hca

As a general rule, you have to reject diamonds that fall below a score of 2. Read here: http://beyond4cs.com/shapes/round/hca-scores/

Also, it is only applicable for round brilliant cut, aka the traditional 57 facets diamond. So any extra facets or fancy cut shape probably can't use it.

Once you done calculating the score, you still have to look into the hearts and arrows and light performance, where most local shops won't be able to provide. So, that's the reason I opt to buy online at WhiteFlash instead of local stores. You can read about it here: http://myengagementringexperience.blogspot.my/. 

Just made the initial deposit for the diamond, 0.63 E VVS2 3EX Non-flour  

[attachmentid=7737810]

Haha, do read my attachment.

It's a good buy.

Curious, may I know why you choose lab grown diamond?

Btw, do share the idealscope, hearts and arrows, aset images!