10 years, 23 countries on 5 continents, 9 countries in Europe, 18 states in USA, 48 provinces in VN 10 years, 23 countries on 5 continents, 9 countries in Europe, 18 states in USA, 48 provinces in VN

Diamond buying guide

Choose to buy Diamonds with GIA's 4Cs

Diamond is a symbol of power and wealth, symbolizing purity & immortal love.

Natural Diamond Flower Gold Ring - AME Jewelery

"Men look at prices
Women look carat"

The GIA - Gemological Institute of America 's 4Cs Diamond Assessment Certificate has the highest value and is circulated worldwide. There are also prestigious gem assessment centers such as AGS - American Gem Society , HRD - Hoge Raad voor Diamant.

Fancy Color Diamond is not in this 'Color Scale' color scale.

GIA Diamond Grading Scales

GIA Diamond Grading Scales

GIA: How to Choose a Diamond

Color grade

Diamonds are generally known to be colorless, but most diamonds mined have a noticeable yellowish and brownish tint, and only a small percentage of them can be classified as colorless or near-colorless. no color. Moreover, even stones with a pale yellow color are very rare to find.

According to GIA, the color of colorless diamonds is graded on a scale of D to Z, with D being the most colorless and Z containing a brown or yellow color that can be discerned to the naked eye. Color is graded under controlled conditions by comparing a diamond with brilliant diamonds of known color, known as host stones.

diamond color grade

diamond color scale

Diamond color scale - HOUSE

The world of diamonds is not limited to only colorless stones, but also rare ones with various colors called “ Fancy Color Diamonds ”.

Clarity grade

The grade of purity represents how difficult or easy it is to see impurities in a diamond under 10x magnification. GIA divides purity grades into 5 groups with 11 grades. Starting from F - Flawless) to I3 - Included.

diamond clarity grade

diamond clarity scale

Diamond clarity scale - HOUSE

Cut grade

The cut grade represents the precision of the angles, proportions, symmetry and polish, which in turn directly affects the fire, luminosity and sparkle of the stone. A diamond with a beautiful color, high clarity, but poor cut will not be of high value. The diamond cut grade is based on 7 factors: Brightness, fire & scintillation (how the diamond appears when viewed face to face), weight ratio & durability (optimum durability and weight), polish & symmetry (quality). quantity of cutting skills). The level is set by the lowest rating the diamond gets for five of the seven elements.

diamond cut grade

Diamond clarity scale - HOUSE

The cut is the most important criterion of a diamond, determining the ability to keep light in the stone, brightness, dispersion ability, sparkle. Fine cutting can significantly reduce (about 15%) the volume of the finished product and is very time consuming. As a result, cutters may intentionally cut worse to keep the diamond heavier.

In the way of cutting, there are many smaller criteria such as: depth and width ratio (the more balanced the better), border size (too thick or thin is not good), culet size (bottom section, the smaller the better). fine), gloss, symmetry. A properly cut diamond will bring out the best in light and fire. If the cut is too shallow or too thick, the diamond will darken and the sparkle will decrease.

diamond cut deep

“Hearts and Arrows” is a way of cutting a round diamond so that the stone looks like it has eight arrows when viewed from above and eight hearts when viewed from below. Such diamonds are more expensive due to intense marketing, not necessarily because of better cut.

Hearts and Arrows Diamond

Weight - Carat weight

The unit that represents the weight of the diamond. The unit used is Carat. One carat equals 0.2 grams or 200 milligrams. In addition, Carat units are also converted into points for diamonds less than 1 carat. 1 carat = 100 points. Diamonds weigh 0.75 carats = 75 points.

A standard cut diamond weighing 1 carat is 6.5 mm.

Diamond carat weight
The heavier the diamond, the more the price increases progressively. You should buy diamonds slightly smaller than even carats (eg 0.95 carats instead of 1 carats), the price will be significantly lower and still look the same big.

The value of a diamond is proportional to its weight or size. Gemstone weight measured in Carats (Ct), 5 Carats = 1.00 grams. Gemstone sizes are measured in millimeters (mm) or cups. Reference table between weights & sizes of different diamond shapes:

diamond carat size

Source: GIA - Gemological Institute of America

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