Learning More on Diamond Carat Weight

Carat is the standard term used for the weight of a diamond and received its name from the seed of a carob tree.   The carob tree, which is native to the Mediterranean region, is an evergreen tree with an edible pod containing seeds.  The carob seeds were used by early diamond traders as counter weights on balancing scales as units of weight for small amounts of diamonds because of their consistent size.  The weight of the carob seed was 200 milligrams and the weight of a carat is exactly 200 milligrams or as it is know today, 0.2 grams.

Diamond Weight and Points

One of the first questions we’re usually asked is “how many carats is it?’ Many believe that the term carat represents the size of the diamond however; carat represents the weight of a diamond.

One carat is divided into 100 points.  So, for example, a quarter carat or 25 point diamond weights .25 carats (cts).   Diamonds weighing over one carat are expressed as carats and decimals.   They are measured to the hundred thousandths of a carat and rounded to a hundredth of a carat.   For example, a 1.25 diamond would be described as one point twenty five carats.

The cost of a diamond is not measured in weight alone.   Several diamonds of the same weight can be priced considerable different.  When calculating the cost of any diamond; clarity, cut, and color are major factors as well.

It is also important to understand that a 2 carat diamond will not look twice the size of a 1 carat diamond.   Since a diamond is three dimensional, the carat weight is dependent on both the diameter and depth.  A 1 carat ideally cut diamond averages approximately 6.45 millimeters in diameter and a 2 carat ideally cut diamond measures approximately 8.15 millimeters in diameter.  This is about 26% more in diameter than a 1 carat however; the price is about 4 ½ times greater.  As diamonds get larger in size they are also more rare and the price increases accordingly.

Weight of Round Brilliant Cut diamonds vs. their size.

Diamonds are always measured in millimeters.  Proportions for ideal cut diamonds shown below.

.25ct                        4.2mm

.50ct                        5.2mm

.75ct                        5.9mm

1.00ct                      6.5mm

1.25ct                      7.0mm

1.50ct                      7.5mm

1.75ct                      7.9mm

2.00ct                      8.2mm

2.50ct                      8.9mm

3.00ct                      9.4mm

4.00ct                    10.4mm

5.00ct                    11.2mm

How big of a diamond should I buy?

Carat weight is a personal preference and is a decision we can assist you with, but ultimately, you will need to decide what is most important to you.   For some, color and clarity are more important than size and customers will sacrifice size to obtain the best color and clarity within their budget.   Others will sacrifice on the color or clarity to get a larger diamond.

Regardless of your choice, as a member of the American Gem Society we will only sell you diamonds that meet our standards for color, cut, and clarity and display brilliantly.

Engagement Ring Budget

Prior to selecting a diamond, we recommend you set a budget.  By doing this first it will allow you to explore various combinations of color, clarity, and size that will not only meet your needs, but will keep you within your budget.

Remember, weight will not always increase the value of a diamond.  When a diamond is improperly cut it may reduce its brilliance.  A shallow cut diamond will have more surface area on the crown and will look bigger than one that is cut deep with more of its weight on the pavilion.  When a diamond is properly cut, regardless of weight, you get the most brilliance, fire, and scintillation which equals value.

Shop all Since 1910 loose diamonds and engagement rings to find the perfect one for you.

Top 10 Places Engagement Rings Are Lost

For a list of the top 10 most common places engagement rings are lost, stolen, or just misplaced we reached out to Jewelers Mutual Insurance Company.

Here is a list of the top 10 most common places in no particular order.

Public Restroom – a little soap will never hurt anything.  It is never a good idea to take your ring off and place it on the counter when washing your hands.  When applying soap, face your palms toward the ceiling and bend your fingers slightly, so if it were to slip it will stop at your knuckle.

Home – just can’t remember where you left it.  Pick one safe place in your home where you can always put your ring.

Work – if you find you take your ring off on certain days or just can’t do certain tasks while wearing it why not hang it around your neck on a nice chain?

Hotel – most rings are left on the night stand, dresser, or even in the room safe.  Hang a quick note on your door and you’ll always remember it on your way out.

At the beach – rings can always be cleaned.  No one likes seeing globs of suntan lotion or pieces of sand in their ring, but looking at that is much better than never seeing it again.

Down the drain – when washing dishes or your hands if you need to take off your ring place it far away from the sink.  Often times rings are left in a cup or ring stand very close to the sink and either can be knocked over easily.

Boating/Snorkeling – rings are lost when doing water sports because your finger shrinks from the cold water.  Whenever possible, leave your ring in a safe place at home or the hotel safe when on vacation.

Shoveling snow – whether wearing gloves or not your ring can easily slip off due to the cold weather.

Airports – every time you go in and out of your bag always check your finger to make sure your ring didn’t slip off.  We already talked about public restrooms!  Also, bringing a small bright colored ring box with you is a good idea.  Should you need to remove your ring when passing through security the box can easily be seen in the security bin.

Dog ate it – and we thought this was only for home work!

Average Dollar Amount of Claims

Accidental Loss (drain, beach, hotel) – $4,250

Crime (robbery, burglary)– $10,500

Damage (chipped stone, prong) – $1,500

Other (flood) – $7,500

Our recommended Jewelry Insurance Company


Shop all Since 1910 loose diamonds and engagement rings to find the perfect ring for you

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