In the following, where there is quoted text it comes from the URL http://everydayrevie...factory-review/
as it was at the time of this post (4 May 2012). Since the internet can be surprisingly volatile, I have saved a pdf copy of the review...
When buying a diamond, ALWAYS make sure that they have a certificate from a reputable diamond grading lab. In this case, it would be GIA. Always go with diamonds that are rated by GIA because they are the industry standard.
This is pretty good advice, but it is factually incorrect. There is no "industry standard" for grading diamonds, and that's at the root of many problems. GIA has its own standards, and it is pretty good at maintaining a high level of consistency in grading colour, clarity and (for round diamonds) cut. There are other labs that are as consistent, but may work to different standards (e.g. AGSL on cut), which are perfectly fine though not directly comparable.
This may seem like nitpicking, and perhaps it is, but it is a good example of how this review is deceptive. At the very least the writer does not know what he/she is talking about and has not bothered to check the facts. At worst - well, let's not go there.
A 2 carat diamond rated by GIA could be rated as a 2.3 carat diamond by a lesser reputable labs such as GRA.
No it could not. This is the one parameter on which the buyer can be quite assured, since there is a well defined worldwide standard for "carat", instruments to measure weight are not expensive and they can be very precise. A jeweller's pocket weighing scales is less than $50 on eBay, and it will tell you clearly the difference between 2.0 and 2.3. 2.30 to 2.29 requires a more precise tool (at $200), but it is easily achievable, and labs typically use scales that measure one thousandth of carat without any problem.
Apart from the questionable grammar, I would also point out that while GRA is not a paragon for consistency and grading reliability, there are other equally bad or worse offenders. Why pick on GRA?
First of all, the Diamonds Factory price for a diamond of the same exact specification is $10,000 less! (see the screenshot of the top row on each)
But they are not the exact same specification AT ALL!
Also, if you look closely, I only have the princess cut selected on the Diamonds Factory website and I have both princess and the round cut selected for the Blue Nile website.
Precisely. It's a pity that a princess cut will cost about 2/3 of a round diamond of the same weight, colour, clarity and (as far as it can be comparable) cut quality. This is because a round requires a significantly larger weight of rough than a princess of the same size (and it can be a little more labour consuming to cut too), and it is a fact fairly independent of the vendor.
This is because Blue Nile only had one princess cut diamond with those specifications. The Diamonds Factory has about 10x the inventory Blue Nile does!
No they don't. As at the time of writing, BN lists 92440 loose diamonds. TDF lists 110,839. That's about 20% more. However, BN only lists GIA and AGS graded diamonds, while TDF also has IGI, HRD and EGL-USA graded stones. Taking those away (as recommended by the reviewer...), leaves TDF at 91,967 - pretty much the same as BN.
The comparison is also unnecessarily specific by restricting the listing to diamonds of exactly 2.00 carats; broadening the search to a more sensible 2.00-2.10 comes up with 15 diamonds on BN and 18 on TDF - basically the same on both, and plenty enough to choose from!
Finally, there is one small but very important snag. GIA does NOT grade princess cuts for cut quality. Thus the "very good" cut grade has been attributed by BN and TDF. Unfortunately, neither company is particularly clear as to how they came to the conclusion, and chances are that the criteria used are not the same, thus marring any comparison (and incidentally, I would not trust either site to grade cut accurately, but that's another story).
I ended up buying from thediamondsfactory.com because they were cheaper, on average about 30%.
And I suppose you would end up buying a bicycle because it is on average cheaper than a Rolls-Royce (or a Hyundai). Which it is - it is healthier and greener too - but it's not quite a valid comparison.
Picking the 2.0x H/VS1 stones selected above, the average price per carat on TDF is $9007; BN is at $9212, so TDF may actually be slightly cheaper on these specific (and probably not perfectly comparable) stones, but it's 2%, not 30%.
I did another test using 1.0x G/VS1 Excellent cut rounds (about 120 stones on each site, more comparable because at least the cut grade is GIA's in all cases and there's far more stones so smoothing variability): here the average price/carat is $9084 on BN and $10068 on TDF, so the conclusion can as easily be reversed - and more: here it's 10%, not 2% - depending on the characteristics of what one is looking at.
Incidentally, there is no 1.00 G/VS1 Excellent cut round on TDF - so who's got more stock?
I relied heavily on the fact that GIA is a trustworthy diamond lab and as long as the diamond had a rating from them, I could go cheaper.
I can't quite follow the logic. GIA will grade a Q-R I2 poor cut just as well as a D FL Excellent cut. The report only helps you to know what you are buying, but there are still significant differences in desirability (beauty, rarity, demand) between diamonds - even with the same grade - and they are generally reflected in the price. Going cheaper in diamonds normally gets you something different, not just cheaper. You may prefer the cheaper stone, or you may not be able to afford the more expensive one, but it is not like buying a standardised, mass-produced item like say a car or a piece of electronic equipment.
[TDF] mine their own diamonds and own their own factories.
Now, do they? And how do you know? Their site does not make any such claim - they only say that they own jewellery
factories, not diamond mines or cutting establishments. They do play on the "manufacturing" label, and I think this is clearly disingenuous on their part - but nowhere do they claim that they mine or cut.
Because they mine, cut and sell all within the same company, they cut out all middlemen.
They don't mine, they don't cut - or at least we have no indication that they do, and as far as I know they don't. This automatically makes them middlemen. I also suspect that they - like Blue Nile - don't actually own any of their diamond stock and act purely
as middlemen in that regard, though differently from BN they may own or control the jewellery making. There's nothing wrong with that - it's what a retailer does.
Of the 120 G/VS1 stones that I picked up for the price comparison, about 20 seem to be advertised by Blue Nile as well. And generally at a cheaper price (by the usual small percentage) than TDF. If they were mining and cutting them, surely their price would be lower? And BN would not have these stones listed for sale?
Blue Nile actually has brick and mortar retail stores throughout the country.
Really? Can you give me one address? One, never mind "throughout the country". They don't, and are quite proud of the fact. Some online diamond retailers also have stores - whether through the country or in one place - but Blue Nile is not one of them; also, FWIW, some of these "brick and click" dealers are cheaper than Blue Nile, again by a couple of percentage points.
Edited by davidelevi, 04 May 2012 - 05:25 PM.