All I need is THE DIAMOND RING, a perfect one, so perfect she wouldn't say NO! After all, diamonds are girl's best friend (a song featuring Marilyn Monroe).
What kind of ring/diamond should I buy for her?
The easiest way to shop for a ring would be internet i.e. online shopping. It gives a lot of options, beyond the regular established brands like De Beers. But first of all, let's see a few basic aspects: color, cut, carat and clarity, known as 4 C's of a diamond. These four factors affect the price very much.
A Diamond Cut (and shape):
Cut is about the symmetry, proportions of a diamond, its width, depth and other geometrical terms, not just its shape. It is about how much light is reflected from the diamond's inside. Light disperses internally among mirror facets and reflects back from the top of diamond, often perceived as brilliance and fire. A shallow cut actually lets the light escape from sides and the diamond appears larger than it is.
A 'round brilliant cut' shape is the standard and most popular. The non-round shapes known as fancy shapes include heart, radiant, marquise, pear, emerald, oval etc.
A Diamond color:
A diamond's 'color grade' does matter a lot in pricing of a diamond. A color in diamonds is not the about red, blue, yellow. These colors matter in fancy diamonds. But a true diamond is actually a colorless one. G.I.A. (Gemological Institute of America) has established color grading classification which starts from D, the finest color (i.e. colorless) up to the last alphabet Z getting progressively more yellow. Yes, yellow!
Colorless diamond is rare, allows more light to pass thru it and hence creates more sparkle. Grade D-to-E are the finest, most desirable, sparkling and attractive colorless(white) diamonds. But grade G-to-I diamonds are also good bargain as their yellow color tint can not be detected easily. A color of diamond is best seen from the side, and not from the top of the diamond.
Grade J-to-M have a faint tint of yellow, but these can be very attractive too if combined with some great complimentary ring. Looking at these grades, a most colorless diamond is desirable, but there are many desirable colors too. More colors can be seen in fancy diamonds, in which, a color( or a darker color) actually costs more.
A Diamond Clarity:
It is the imperfections, internal (inclusions) and external (irregularities) under magnification. Its scaled as below and is the easiest factor to decide if provided, FL-IF being the best clarity rating.
FL-IF: Flawless - Internally Flawless
VVS1-VVS2: Very Very Slightly Imperfect
VS1-VS2: Very Slightly Imperfect
SI1-SI2: Slightly Imperfect
But even a VVS, VS and SI clarity can be a good choice. A diamond can be attractive even in this clarity range as long as the inclusions are not visible to naked eye.
A Diamond Carat (or weight):
Carat (and not karat as used for gold purity) is unit of weight of the precious stones in general. Carat is related to weight and size of a stone while Karat relates purity or impurity in case of Gold. This is due to difference in specific gravity of stones. For same carat weight, a diamond is smaller than an Emerald and bigger than a Ruby. This is by far the most price sensitive factor, as the price goes up exponentially with increasing carat weight.
Finally, slender and small fingers can make even a 1 carat stone look big!
In addition to these 4 C's of diamonds, there is one more, required in diamond market.
A Diamond Certificate:
A certificate gives you the exact measurements, weight, cut and quality of a loose diamond. There are many, but Gemological Institute of America (GIA) and the American Gem Society (AGS) are the two most widely regarded and recognized diamond grading labs in the world. The advantage of GIA/AGS certificate is that the certificates of many sellers (and their products) can be viewed online.
Bottomline:
Online shopping can be very easy and authenticate with GIA/AGS certified diamonds. Otherwise, a visit to shop is necessary to make sure what you see is what you get. Besides, you may not recognize difference between two different quality diamonds unless you are told their prices, i.e. higher price doesn't necessarily guarantee satisfaction. The choice of ring is important as well and complimentary to the diamond.