How To Choose A Diamond – Diamond Buying Step by Step Guide

LAST UPDATE ON: March 1st, 2021

I can not tell you what to buy, but I buy my wife the biggest, brightest, whitest, eye clean diamond (with some blue Fluoro); usually D-F, SI1. I know what to look for to see lower color, but at 50+, I have no hope of seeing an SI1 inclusion! If I had a lover, she would probably get K I1 ;-).

Sharp eyed younger or “fussy folk” might prefer higher clarity, but smaller size. High color and high clarity combinations cost a lot more than high color and medium clarity or medium color and high clarity. Most people can see the color difference between I and D, in good lighting; very few can see the difference between IF and SI1.

You may not mind seeing an inclusion or two, or you may find low color diamonds “warmer”. It is a good idea to view a range of diamonds.

Carat weight costs the most, especially “Magic Weights”
(like 1.00ct, 2ct, 1/2ct etc). “Undersizes” like 0.90ct and 0.45ct cost a lot less. If magic weights do not impress you, search for undersize; but they are rare, there are about 5% as many .99ct diamonds as 1.00ct stones.

A badly cut 1.00ct D Flawless costs more than twice as much a bigger diameter (spread), more sparkly Ideal Cut .90ct F SI1.

4 C’s	Effect on
4 C’s	$	Beauty
Cut	$	Most
Color	$$	A lot
Clarity	$$$	Some
Carat	$$$$	?

50 years ago only very rich people could afford big diamonds. They often bought high clarity on the recommendation of a trusted jeweler (who stocked on the advice of his trusted supplier). Today we see more sales of F-H VS2 to SI1 diamonds.

A consumer is shown 2 diamonds – D IF and G SI. “They both look the same to me, but you want 3 times as much for this one? Man are you kidding me?!”

Demand for high end commercial grade stones (D-H, VS-SI) will probably grow in my opinion and that means they will retain value and liquidity.

Religion or culture may be important; clarity in some cultures = purity = divine powers bringing good luck.

Shape. Round brilliants are the most sparkly and most popular shape; therefore rounds have the highest liquidity should you ever need to resell or trade up. Various fancy shapes come and go in popularity (and rise and fall in value). Right now, for engagement rings, Princess cuts are hot. Princess cuts have more small sparkles than round diamonds; but below 1ct, as we age, our ability to discern those tiny more frequent sparkles reduces. Princess cuts are more prone to chipping on the edges during wear and on the points during setting. Fore-warned is to be fore-armed.

Investment Diamonds. Go see an investment advisor or buy property or shares. When you make enough money from your investments, buy a nice diamond 🙂

Here are some other people’s suggestions.

Priority

Recommendations

Size Only
You can live with a yellowish diamond with a few black spots! The cut should be in the 54% to 60% total depth range with a thin to very thin girdle (this can still rate well on the Cut Adviser). Look for a +60% table (keep below 65%)

Cut	Spread
Carat	magic weights
Clarity	I2
Color	L – M

Size, then Quality
Your friends can’t see the inclusions if you keep moving it. Slightly yellowish in daylight or office lighting. Cut – as above.

Cut	Spread
Clarity	I1 – SI3
Color	J – K

Both Size and Quality
Your diamond must look clean to the eye, white and sparkly. It should have a good ideal-scope image etc.

Cut	BIC
Clarity	SI1-2
Color	I up

Quality Only
You want to impress people with the jargon, or you want the best money can buy because the diamond is a symbol of your love. Inclusions must be hard for you to see through a microscope or a 10X loupe. The diamond must blow your friends away with its icy whiteness. It must be beautiful with a Cut Adviser rating of around 1.0 to 2.0. It probably should have a branded cut name.