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Lab Grown 3-Carat Diamond Rings

There is nothing quite like a 3-carat diamond ring - and from size to shape- we break it all down below for you.

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What is Carat Weight?

One of the 4Cs, carat weight is a unit of measurement that is utilized to determine the weight of diamonds and other precious gemstones.

Believe it or not, the origins of a diamond's carat weight can actually be traced back to ancient times when early gem merchants would measure the weight of precious gemstones with uniform seeds of the carob tree. The carob seed was unique in that each seed was relatively uniform with the others and was roughly equal to 200 milligrams in weight.

In 1913, carat weight was standardized internationally and adapted to the metric system in America. Essentially, one carat equals 0.2 grams (0.0007 oz) and is measured to three decimal points and rounded to the nearest hundredth to ensure for incredibly precise measurements. Three carats would then equal 0.6 grams or roughly the weight of a standardized pencil!

Is a Diamond's Carat Weight the Same Thing as Diamond Size?

While they may seem as if they mean the same thing, a diamond's carat weight is not the same as the diamond's size.


The size of a diamond takes into account the height and the width of the diamond to determine how much space the diamond takes up. The carat weight of a diamond, on the other hand, only measures the weight of the diamond.

What's more, two diamonds in different shapes that have the same carat weight can actually appear to be two completely different sizes. This is because the shape of the diamond can affect how much space the diamond takes up. For example, an oval-cut diamond has more surface area than a round brilliant diamond. So while they may have the same carat weight, two differently-shaped diamonds could actually look quite different in size.

How Does a 3-Carat Diamond Differ in Size than a 2-Carat Diamond?

Because differently shaped diamonds can appear larger or smaller than diamonds of the same carat weight, we will be comparing round brilliant diamonds instead of princess-cut diamonds and emerald-cut diamonds for example.

A 2-carat diamond engagement ring will be 8.1 millimeters across and a 3-carat diamond engagement ring will be 9.3 millimeters across. This is a difference of 1.2 millimeters.

While carat weights with larger gaps will always seem much bigger, as is the case when comparing a 2 and 3-carat diamond engagement ring, when you compare the carat weight of diamonds closer in size it becomes harder to tell the difference in size.

How Does a 3-Carat Diamond Differ in Size than a 1-Carat Diamond?

Because there is a much larger gap in size between a 1-carat diamond engagement ring and a 3-carat diamond engagement ring, there will be a noticeable difference in size. A 1-carat fine jewelry engagement ring will appear 6.4 millimeters across while a 3-carat ring size will appear 9.3 millimeters across. That's a difference of almost three millimeters!

How Much is a 3-Carat Lab Created Diamond Ring?

A general rule for pricing diamond rings is that as the diamond's weight increases so will the price. And while this is true, there are also a variety of factors that can affect the cost of a lab created diamond ring.

The shape of the diamond and how much rough diamond was maximized in cutting the shape can determine how expensive the diamond will be. For example, round brilliant diamonds are the most expensive diamond shape, not only because they are the 'standard' cut as outlined by the Gemological Institute of America, but because they also create the most diamond waste of any of the shapes.

When compared to fancy-shaped diamonds such as radiant, princess, or oval-cut lab grown diamonds, of similar carat weight, the round diamond will always be more.

Another factor that determines the cost of the diamond ring is how your chosen diamond is graded in the other 4C categories of cut, color, and clarity. The higher the diamond scores the rarer and ultimately, more expensive, the diamond will be.

Finally, a lab created diamond engagement ring will be priced according to the precious metal utilized, yellow gold vs platinum for example, and the style of engagement ring, as seen by classic round solitaires being often priced less than halo settings.

At Clean Origin, our 3-carat lab created diamond engagement rings can range from to a breathtaking $2,914- 3-carat emerald-cut solitaire diamond engagement ring in yellow gold to an $18,165 for a 3-carat round brilliant excellent scoring diamond set in a bedazzled vintage-style platinum ring and everything in between.

How Big is a 3-Carat Diamond Ring? 

A 3-carat round brilliant diamond ring will be 9.3 mm across. If you're looking for the largest looking 3-carat lab grown diamond then you can't go wrong with an oval or Marquise-shaped diamond which will appear 11.5mm long x 7.5 mm across and 14mm x 7mm.

Ultimately, when browsing different diamond shapes, try not to focus on size as much as your personal style and preferences and you won't go wrong!

Why Choose A Lab Grown 3-Carat Diamond?

Lab created diamonds provide all of the sparkles of mined diamonds without any of the negative ethical and environmental impacts. A conflict diamond is a diamond that is a diamond traded to illegally fund conflict in war-torn areas. And while the Kimberley Process was passed in 2000 to stop the trade of conflict diamonds, it is still a nearly impossible process to ensure that your mined diamond is 100% conflict free.

Lab grown diamonds are not only guaranteed conflict-free diamonds, they're also better for the environment. On average, mined diamonds displace about 1700 tons of earth for just one carat of diamond. This soil displacement leads to deforestation, soil erosion, and the destruction of farmlands. On the other hand, a premium lab grown diamond from Clean Origin is perfectly environmentally friendly.

Finally, because lab grown diamonds have a shorter chain supply they are also more affordable. On average, a lab grown diamond or other fine jewelry from Clean Origin is 20-40% more affordable than mined diamonds.

With environmentally friendly lab grown diamonds at Clean Origin, your three carat diamond ring is in your grasp at last!

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