How to Choose a Diamond: Four-Minute GIA Diamond Grading Guide by GIA

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if you're shopping for a diamond you

probably have a lot of questions like

how can I be sure that what I'm

purchasing is a real natural diamond how

do I know if the diamond has been

treated the key to understanding a

diamond and its value is to understand

the four attributes that all diamond

share color clarity cut and carat weight

also known as the four seeds the

Gemological Institute of America or GI a

developed the four C's in order to

create a universal language when it came

to the difficult task of determining

diamond quality established in 1931

nonprofit GI a is the largest and most

respected Institute of Gemological

research and learning in the world GI a

created not only the four C's but also

the international diamond grading system

the grading standard used worldwide

let's follow a diamond through the steps

in the GI a grading process and see how

its evaluated scientific precision is

critical as expert gemologist examine

each diamond under tightly control

lighting and viewing conditions each

diamond travels through the lab in a

nondescript case to be sure that it is

graded consistently and objectively

first it is tested to determine whether

the diamond is natural or lab-grown if

the diamond were synthetic it would be

pulled out of the queue and subjected to

a separate procedure next it's on to the

four seeds the first C is color when it

comes to diamonds the less color the

higher the grade the GI a color scale

classifies diamonds from D colorless to

Z light yellow or brown at the gie a lab

a color grade is determined by comparing

each diamond to a master set of diamonds

that represent the color grades on the

GI a scale the second C is clarity the

GI a clarity scale includes 11 clarity

grades ranging from flawless to I three

flawless indicates that there are no

inclusions or blemishes visible at ten

times magnification a grade of I three

is for diamonds with inclusions that are

obvious to the naked eye a ten times

magnification loop and a microscope are

used to see and plot the inclusions

since no two diamonds are exactly alike

this unique plot helps identify a

particular stone

graders also look to see if there is any

evidence that our diamond was treated to

improve its clarity the third C is cut

the GI a cut scale is used for round

brilliant cut diamonds and consists of

five grades ranging from excellent to

poor you may think of cut is the shape

of a diamond like square cut or round

however there is much more to cut than

the basic shape how a diamond is cut and

polished directly affects the amount of

sparkle and brilliance that comes off

the stone each diamond is placed in a

highly precise measuring device that

rotates the stone 360 degrees to

optically capture hundreds of

measurements and facet angles G ia

scientists developed a comprehensive

system that factors the diamonds

proportions as well as its culet size

girdle thickness polish and symmetry

descriptions and generates a GI a cut

grade the fourth C is carat weight one

carat equals 200 milligrams or one-fifth

of a gram in weight at the GI a lab each

diamond is placed in a sealed chamber

and weighed on an extremely precise

electronic scale to the fifth decimal

place the diamonds four C's along with a

wealth of additional information appears

on its GI a grading report a GI a report

is the most technologically advanced

diamond evaluation possible it provides

a unique blueprint of a diamonds

attributes and a permanent record of its

quality as an added security feature

diamonds graded at GI a can be

microscopically inscribed along the

girdle where their unique GI a report

number the act of choosing your diamond

should be exciting and enjoyable just

keep all the four C's in mind color

clarity cut and carat weight and be sure

to always ask your jeweler for a GI a

report your ultimate assurance of your

diamonds quality