The clarity of a diamond is decided by the fact of how clean its inside is. And so, its value is raised by the fewer imperfections it has.
What flaws you do see in diamonds comprise blemishes and inclusions, which can tarnish its overall beauty. Located in specific places, these can bring down the value of the diamond accordingly. This factor is determined by gemologists using a magnification loupe of 10x magnification.
Diamonds are gemstones that used to have imperfections in them, which were then treated to obscure them. You get diamonds these days, which are “Clarity Enhanced”, from jewelers such as Beverly Diamonds. The process is akin to filling a crack on your car’s windshield. The good thing about clarity enhanced Beverly diamonds stones are that they look almost the same as flawless ones, but cost considerably less.
Most people never get clarity enhancing done on the stone they purchase, because chances are no one is going to actually check it out for flaws with a microscope. The only problem is that the more flaws the stone has, the less clear it will look. With enough of these in the diamond, people would not actually need to see each flaw to know there are some. The alternative to Clarity Enhancement is laser treatment, which is a lot more permanent too. However, it is also more costly.
There are some things that can make the filling in a Beverly diamonds stone to come out. Exposure to fire can bring out the filling in a clarity enhanced diamond, where boiling acid is also not conducive to the filling staying in. Re-cutting to define the shape can shake the filling loose and bring it out as well. So, if you ever let a jeweler handle the stone, make sure that they know about the Clarity Enhancement before they start work on it.
For a Beverly diamonds stone that looks clearer when you wear it, you will need a clarity grade of VS2 or higher. If however, you think that a few blemishes and inclusions in diamonds are not worth bothering about, then a standard SI grade would be sufficient to get you the look you want in the diamond. Most customers can find no complaint with this, although many prefer the VS2.
All this comes down to personal taste, and at the end of the day, that and budget should decide the diamond you buy.