newbie question RE HCA

[Miles]

All,
new on this site and have learned a great deal reading the tutorials. I''m in the market for an engagement ring and am trying to learn as much as possible prior to purchase. Given the various rating systems and tools, it seems that buying via an online vender that is pricescope sanctioned removes some of the risk, but given my novice background on diamonds I''m still a little apprehensive. For instance, I just came across some negative info RE the HCA at the web site of Diamond Brokers of Florida where they essentially claim that HCA is not useful at all. http://www.dbof.com/why-the-hca-does-not-work.htm
What is the position of the forum experts on this?

DA

 

[Regular Guy]

DA,

I''m a long time reader and writer here, and haven''t heard about DBOF in a long time. I went to read their text, and see it is unchanged from a long time ago.

You could do us a service, by calling them, and asking them, in the genuine way you have the question...how they see what HCA does, and describe at the beginning of their article...

"For the last few years, there has been a system that claims to give visual performance of diamonds it never sees based on punching in a few numbers which are then spit back out as supposedly accurate visual results?!"

...ask them how they see what HCA does, as fundamentally different than the system GIA now uses to grade cut for diamonds?

BTW, welcome to Pricescope!

 

[Miles]

Ira,
thanks for the info and the welcome. sure, I was planning on giving them a call anyway and will ask them. The text they have there is very long and seems to be a lot of hand waving, trying to dismiss the importance of the underlying mathematics and physics. Whenever I see something like that I get a bit worried RE the source. On another forum a member recommended them highly so it''s at least worth checking out.
Cheers,
DA

 

[Fly Girl]

Fundamentally, the HCA is a rejection tool. It never claims to be able to select a beautiful diamond, due to the numerous assumptions that it has to make. It simply allows you to look at a list of diamond specs, and make an educated guess as to which ones are worth further investigation. And, this is quite useful.

Enjoy learning about diamonds!

 

[Garry H (Cut Nut)]

The most interesting development is that GIA's system is on the same basis as HCA, but with minor facets added.
The only visual examination GIA gives that is cut related is the girdle thickness is done by humans.
But no one at GIA looks at the cut of a diamond in their grading process.

 

[Miles]

thanks for the info. has anyone here had any experience buying from them?

 

[oldmancoyote]

They seem to have a reasonable reputation on other forums, and they provide a more than reasonable amount of info on their stones.

If you read through the DBoF article, it seems that they think of/position the HCA as a tool to predict light return/beauty. Which I think no-one here is advocating. How much this is a misunderstanding on their part, and how much it''s deliberate misinformation, is hard to say.