SI1 Diamond Clarity

SI1 Diamond Clarity 2018-08-17T15:35:34+00:00

Did you ever wonder why on both James Allen and Blue Nile there can be such a wide discrepancy of prices for what at first glance look like similar diamonds?  As a test I did a search for a round 1.00 carat Ideal cut H-SI1.  Blue Nile returned 3 results (see screenshot below).  Why in the world would there be a nearly 10% price difference for 2 of these diamond?


In order to understand why (and to see why SI1 diamond clarity can be a great value) it is important to understand how GIA (and others) determine a clarity grade. The grading that is given is for the overall clarity of the diamond- not for the severity of any given inclusion. You will find some diamonds that have a single visible black spot smack in the middle of the table (stay away!) and you will find others that have several smaller blemishes that are almost not noticeable but together add up. Because the total cumulative number of these small spots is above a certain threshold GIA will grade this diamond as an SI1. As a consumer this is a great opportunity for you to buy a clean diamond at a lower price! (For more on this topic read my general Diamond Clarity page).

In the Blue Nile example I gave at the beginning of this page without actually seeing the diamond  you would never know why the 10% price difference exists and you may think you found a great deal when in fact you may have just bought a diamond that when you look at it all you will see is the blemish dead center!  At least on James Allen you see the actual diamond photos and can see for yourself (or ask me to help you) if you found the deal you wanted. This is why I stress over and over to buy online – but only if you can see the actual diamond photos.

Here are some real world photos that show the various types of SI1 diamonds (these are all courtesy of James Allen). Notice how the one on the left appears clean- there is a slight feather at around 1:00 which will be invisible to the naked eye. This is a diamond I would have no problem recommending and is a great value over a VS1 or VS2. On the other hand the black inclusions on the diamond on the right stand out immediately and I would not recommend this diamond. Click on either one for a larger picture.


Note: Buying a diamond can be a nerve-racking experience. If you want my expert advice on buying the best diamond just drop me a note and tell me what you are looking for and how much you want to spend and I will get back to you with my personal recommendations for a beautiful stone that fits in your budget. This is a FREE service, doesn’t cost you a dime extra, (in fact I am sure that it almost every case I can save you lots of money) and there is absolutely no commitment.

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