Carat - The easiest of the five c's to understand. The "carat" is a measure of weight. The larger the diamond is the larger the carat weight figure will be. Many times you will hear the term "points" in reference to diamond weight. If you think of 1 carat as 1.00 dollar, then a ¾ carat diamond is .75 cents or 75 "points". It is expressed as .75 ct. When you see ".ctw" after a weight it means that more than one diamond adds up to a total combined weight of three quarters of a carat. CTW means "carat total weight".

It is important to understand that the value of diamonds increases exponentially. By that we mean that a one carat diamond (1.00 ct) can cost much more that simply twice the price of a half carat diamond (.50 ct) even though it weighs twice as much.

Emerald

Weight in Ct.	0.50	0.75	1.00	1.25	1.50	2.00	2.50	3.00
Emerald
LxW in mm.	6x4	7x4.5	7x5	8x5	8.5x5.5	9x5.5	9.5x6	10.5x6

Marquise

Weight in Ct.	.04	.06	.08	.11	.15	.20	.25	.38	.50
Marquise
LxW in mm.	3x1.5	3.5x1.8	4x2	4.5x2.2	5x2.5	5.5x2.8	6x3	7x3.5	8x4

Oval

Weight in Ct.	0.50	0.75	1.00	1.25	1.50	2.00	2.50	3.00
Oval
LxW in mm.	6x4	7x5	7.5x5	8x5.5	9x6	9x6.5	9.5x6.5	10.5x7

Pear

Weight in Ct.	0.50	0.75	1.00	1.25	1.50	2.00	2.50	3.00
Pear
LxW in mm.	7x4	8x5	9x5	9.5x5.5	10x6	11x6.5	12x7	13x8

Princess

Weight in Ct.	.02	.05	.10	.16	.27	.41	.52	.65
Princess
Length in mm.	1.5	2.0	2.5	3.0	3.5	4.00	4.50	5.00

Round

Weight in Ct.	.02	.03	.05	.10	.20	.25	.35	.40
Round
Dia. in mm.	1.8	2.0	2.4	3.0	3.8	4.1	4.5	4.7

Trillion

Weight in Ct.	.05	.07	.12	.16	.25	.32	.40
Trillion
Length in mm.	2.5	3.0	3.5	4.0	4.5	5.0	5.5

What size (carat) diamond should I buy?

• First figure out your budget. Some will say that two month salary is what you should spend on a diamond. I say its bunkers. You spend however much you are comfortable spending. Do not listen to industry experts when it comes as to how much you should spend on the diamond, instead consult your own bank account I am almost certain that source of information will be much more honest with you.
• When making a decision on size of the diamond keep in mind that you are dealing with balance between the quantity and quality. You may pay for instance $1000.00 for a two carat diamond or pay $5000.00 for a one carat diamond. This decision is strictly a personal preference. I for instance went for smaller rock which had nearly flawless clarity
• Here is a trick that may help you. Slender fingers make the diamond look larger than it really is.