How Big is a Twelve Carat Diamond?

Around for quite some time, but we overlook the importance of the stone’s quality when answering it. Except for scarce and expensive diamonds, determining the actual value solely based on its carat size can be difficult. Fortunately, there are some guidelines to follow. The truth is that while many websites and jewelry stores provide information on carat size, the number on the label cannot be relied upon solely.

Fortunately, there are other methods of determining the weight of a diamond besides using its carat weight. One method of estimating the size of a diamond is to compare it to a commonly encountered object. In the jewelry industry, a carat is a unit of weight measurement, with one carat equaling 200 milligrams. Thus, a 12-carat diamond would be approximately twice the size of a two-carat stone.


Diamond is a mineral that is composed entirely of carbon. It is the most difficult naturally occurring substance known to man, and it is also the most popular gemstone on the planet. Diamonds are used in a variety of important industrial applications because of their extreme hardness and strength.

While carat weight can provide an accurate estimate of the size of a diamond, it’s important to remember that it doesn’t always correspond to the size of a diamond in the real world. The truth is that different cuts come in various sizes and shapes. The exact diameter diamond will appear to be different from a smaller diamond, even though they are both the same size. The length, width, depth, and surface of a stone should be considered when determining its size.

The next step is to go to a diamond shop and have the size of the diamond measured there. If you do this, you will have a general idea of what you are looking for. Make sure to examine the diamond’s clarity, as this is what determines the value of the diamond. When we talk about clarity, we refer to the stone’s clarity, and inclusions can be either visible or invisible. It is critical to consider the carat weight of the diamond, regardless of its clarity.


The definition of a metric “carat” is 200 milligrams, and 100 ‘points’ are divided into each carat. This enables measurements to be made to the hundredth decimal place. Jewelery can use the ‘points’ alone to describe the weight of a diamond under one carat. A 0.25-carat diamond, for example, might be referred to as a ‘twenty-five pointer’ by the jeweler. Carats and decimals are used to express diamond weights greater than one carat. ‘One point oh eight carats’ is how a 1.08 carat stone is described.

When all other factors are equal, the price of a diamond rises with its carat weight because larger diamonds are rarer and more desirable. However, depending on three other factors of the diamond 4Cs: color, clarity, and cut, two diamonds of equal carat weight can have vastly different values (and prices).

While you now understand what carat means, keep in mind that the value of a diamond is determined by all four Cs, not just carat weight.

12 carat =  2.4 mm

        MM                     2mm        3mm       4mm    5mm   6mm     6.5mm      7mm        8mm               10mm

     Tourmaline     .04 ct        .12 ct          .24 ct     .45 ct       .75 ct     1.28 ct      1.55 ct       2.00 ct            3.00

12 Carat Diamond Shapes

Every diamond is cut differently, resulting in significant differences in the length and Width of a diamond. However, here are the approximate sizes for the various shapes of Excellent cut diamonds:

  • 14.95 mm by 15.05 mm round brilliant cut (Length by Width)
  • 14.10 mm by 15.75 mm heart shape (Length at the maximum of the two lobes at the top by Width maximum from the top most to the bottom-most part of a heart).
  • 17.80 mm by 13.10 mm oval shape (Length by Width)
  • 15.70 mm x 11.30 mm Emerald Shape (Length by Width)
  • 12.80 mm x 12.90 mm Princess Shape (Length by Width)
  • 20.20 mm x 13.40 mm Pear Shape (length by Width)
  • 13.80 mm by 13.10 mm cushion shape (Length by Width)


A 12-carat brilliant-cut diamond ring leads bonham’s Jewelry Auction. On June 19, I sold a 12.13 carat cut-cornered rectangular modified brilliant-cut diamond ring at Bonhams Fine Jewelry auction for $482,500. The total amount raised at the auction was $5.3 million.

You can get anywhere from 20% to 70% off the retail price of your diamonds by trading with just a few of your friends. The price varies greatly depending on how you go about selling your ring. If you sell it on consignment, you’ll get a different price than selling it to a dealer.


All things in a stone that obstruct the free passage of light are covered by clarity. Gem graders consider transparency, inclusions, and surface blemishes when evaluating clarity. . You can find inclusions in many gemstones, including almost all diamonds. However, some are so minor that they have no bearing on grading.

Minerals, some in crystal shapes and others in long needle shapes, and twinning wisps that form inside a stone are inclusions in diamonds. Gem cutters usually try to cut a piece of diamond rough as cleanly as possible to produce a stone free of inclusions. In most cases, inclusions cannot be removed, though some treatments in faceted gems attempt to reduce their impact.

The fewer inclusions a diamond has, the more valuable it is. On the other hand, inclusions in diamonds are prized by geologists because they reveal a lot about the Earth’s formation. (The newest diamond dates back 900 million years.) Some inclusions can be pretty lovely and intriguing as well. Garnet or diopside, as well as mini diamond crystals, can be found in diamonds. Diamond inclusions that contain diamond inclusions are found in some diamonds! Like a Russian matryoshka doll, they all fit inside each other. Included diamonds can be exciting additions to mineral or gem collections.

Is Clarity 12 a Good Clarity Grade for a Diamond?

That GIA standard specifies that diamond color D is the “best” color for a diamond. (See this page for more information on D color diamonds.) IF or FL clarity grade diamonds are the closest match for D color diamonds in terms of rarity and price. D color diamonds are scarce, and their price reflects this rarity. Crystallization grades I2-I3 Diamond clarity grades I2-I3 Diamond clarity grades I2 diamonds are one grade better than I3 diamonds. As the lowest clarity grade on the scale, an I3 diamond has even more visible inclusions than an I2 diamond and will be more difficult to distinguish from an I2 diamond. As a result of these imperfections, we do not recommend I3 diamonds because they detract from the diamond’s brilliance and aesthetic appeal.

What is the Size of a Large Diamond?

Assuming a 1-carat stone is used in the average-sized engagement ring, it is safe to say that anything more significant than that is considered large. When diamonds reach a weight of 2 carats or more, most people consider them to be significant. Rings of this size, on the other hand, are less common. This is one of the reasons why most people consider a 2-carat diamond to be a large diamond.

What Exactly is the Point of a Round Cut?

It has 58 facets (including the culet) and provides exceptional white light reflection, also known as brilliance, due to the shape’s unique facets arrangement. As a result of their classic and timeless appearance, Round Brilliant Cuts are frequently found in engagement rings, necklaces, and other fine jewelry pieces.


A twelve-carat diamond is roughly the same size as a human hand in circumference. The jewelry will completely encircle the total physical size of the object. This means that the diamond’s surface area is only 25 percent of its actual size, which is significantly reducing. It will, however, appear to be significantly larger than it is. Using a diamond size chart can assist you in making the best decision when purchasing a ring that contains a diamond that is less than twelve carats in weight or size.

The most straightforward method of determining a diamond’s carat weight is to look at its Cs. Carats are measured in carats, divided into 100 equal parts called ‘points,’ which are used to measure diamonds. One hundred points are contained within a one-carat diamond. The size of diamonds can be measured as a fraction or in decimal numbers, so the percentages are only a rough guideline. In the end, however, you should select the option that is most appropriate for you.