Diamond Education & Glossary
picking loose round brilliant diamonds with tweezers
loose princess, round, and cushion diamonds on white table
loose diamonds - round and emerald-cut shining in glassy light
loose diamonds on white table with red fabric lining
remarkable origin stories
Diamond Sources

Can you tell the difference between a lab-grown and an earth-mined diamond? The simple answer is no. Both appear to be visually identical. A lab-grown diamond has the same qualities and chemical makeup as a natural diamond.

[Blog] Lab or Natural?
bright white diamonds on contrasting black carbon rocks with one round diamond being lifted with tweezers
Color, Clarity, Cut, Carat
The 4C's

Diamonds can be used to increase the value and significance of various pieces of jewelry, including engagement rings, wedding bands, bridal sets, necklaces, bracelets, and others. Grade and quality are used to evaluate diamonds. The primary factors used to determine whether a stone is the best match are the "4 C's": cut, color, clarity, and carat.

Before choosing a specific piece, the 4 C's of diamonds may help you decide what to look for in a center stone and side stones.

[Blog] Learn Your C's

What's Your Angle?

The Crown & Pavilion

Crown Height

The portion of the diamond that extends from the girdle to the top of the table is called the crown...

Crown Angle

The crown facets behaving as prisms play a crucial role in light dispersion...

Pavilion Depth

The amount of light returned by the stone is affected by the pavilion's depth...
[Blog] Learn More
Trusted Diamond Grading Organizations
Certifications

From GIA to IGI. A diamond certificate acts as a formal report on a stone's specifications. A diamond's internal markings, inclusions, and other properties are used to identify it.

[Blog] How to Read a Cert
Kobelli Custom Tailored Basic Diamond Ring - featuring a radiant-cut diamond of excellent symmetry
Beyond the C's
Polish & Symmetry

The significance of a diamond's polish and symmetry in evaluating the overall quality of a diamond is roughly 50%. These two criteria are included in diamond certificates, also known as are grading reports. To obtain an ideal stone, the stone must have the proper polish and proportions...

[Blog] Learn how it's graded
round brilliant colorless stones on wooden surface
to glow or not to glow
Fluorescence

Diamond fluorescence is a trait that can make lower-color diamonds (I-M) appear whiter and more vibrant, often for a lower price. While it can enhance warm-toned stones, very strong fluorescence may cause a milky or hazy appearance in high-color (D-F) diamonds, slightly reducing their value.

When a diamond is exposed to long wave Ultra-Violet (UV) light, the amount of a colored glow (often blue) that is visible is referred to as diamond fluorescence...

[Blog] Read on

Diamond Shapes


Round Shape Cushoin Shape Radiant Shape Pear Shape Asscher Shape
Oval Shape Princess Shape Emerald Shape Marquise Shape  Heart Shape  




Round

Classic and brilliant, round cut stones are a popular choice for engagement rings in both traditional and modern settings. | Shop Kobelli Round Centered Jewelry.
Approx. Millimeter
Approx. Carat Weight
4
0.25
5
0.5
6.5
1
7
1.25
7.5
1.5
8
2
9
2.5
9.5
3
9.7
3.5
10
4
10.5
4.5
11
5


Oval

Perhaps the second most popular diamond cut next to round, oval shapes are brilliant, slimming and arguably the most fashion forward choice for engagement rings. | Shop Kobelli Oval Bridal & Fine Fashion Jewelry.
Approx. Millimeter
Approx. Carat Weight
6.5 x 4.5
0.5
8 x 6
1
9 x 7
1.75
10 x 7
2
11 x 7.5
2.5
11.5 x 8
3
12.5 x 8.5
3.5
13 x 9
4
13.5 x 7
4.5
14 x 9.5
5


Cushion

One of the most unique stones on the market, as well as a Kobelli customer favorite, particularly on our halo rings, cushion cut stones are between a round brilliant, old mine and radiant, with rounded corners for a comfortable look and feel.

Cushion stones vary from elongated to squarish. Kobelli hand selects each of our cushion stones to best fit our designs for the most flattering outcome. | Shop Kobelli Cushion Wedding Jewelry.
Approx. Millimeter
Approx. Carat Weight
4.5
0.5
5.7
1
6.2
1.25
6.5
1.5
7.3
2
8
2.5
8.3
3
8.7
3.5
9
4
9.5
4.5
10
5


Princess

A traditional stone cut with remarkable brilliance and sparkle, princess cut diamonds are the square alternative of the round brilliant. | Shop Kobelli Princess Luxury Jewelry.
Approx. Millimeter
Approx. Carat Weight
4.4
0.5
5.5
1
5.9
1.25
6.3
1.5
7
2
7.5
2.5
8
3
8.3
3.5
8.7
4
9
4.5
9.3
5


Square Radiant

As the name implies, radiant cuts give off magnificent radiance and sparkle with its intricate faceting and stunning flair.

A popular choice for our custom orders, Kobelli customers are absolutely in love with this dazzling stone cut. | Shop the Kobelli Radiants.
Approx. Millimeter
Approx. Carat Weight
4.3
0.5
5.5
1
6
1.25
6.5
1.5
7
2
7.5
2.5
8
3
8.5
3.5
8.8
4
9
4.5
9.5
5


Rectangular Radiant

Rectangular radiant cut diamonds showcase exceptional brilliance through their distinctive facet pattern, delivering captivating sparkle and light performance. This versatile shape combines the elegance of emerald cuts with the fire of brilliant cuts, creating a stone that commands attention from every angle. Perfect for those seeking a diamond that balances sophistication with dazzling visual impact.

A popular choice for our custom orders, Kobelli customers are absolutely in love with this dazzling stone cut. | Shop the Kobelli Radiants.
Approx. Millimeter
Approx. Carat Weight
5 x 3
0.31
4.5 x 3.5
0.34
6 x 3
0.41
6 x 4
0.50
6.5 x 4.5
0.75
7 x 5
1.00
7.3 x 5.5
1.25
7.5 x 5.8
1.50
8 x 6
2.00
8.5 x 6.5
2.25
9 x 7
2.50
9.5 x 7.5
3.00
10 x 7
3.31
10 x 8
3.50
11 x 9
5.05
12 x 9
6.06
11.5 x 10
6.45
13 x 9
6.54
12 x 10
6.79
14 x 10
8.47
13 x 11
9.33
13.5 x 11.5
10.19
15 x 11
11.48
14 x 12
12.14
16 x 12
14.22


Emerald

Beloved for its Art Deco appeal, clean cuts and sharp appearance, emerald cut stones give off a breath of fresh air with its gleaming sparkle, unique from that of the more traditional cuts and just as stunning. | Shop Kobelli Emerald Shape Creations.
Approx. Millimeter
Approx. Carat Weight
5.5 x 4
0.5
7 x 4.5
1
7.5 x 5
1.25
8 x 5.5
1.5
8.5 x 6
2
9 x 6.5
2.5
9.7 x 7
3
10 x 7
3.5
10.7 x 7.5
4
11 x 6
4.5
11.5 x 8
5


Pear

Pear cut diamonds have long been loved for their royal ties and long, slender shape. A challenging stone to cut and set, pear cut jewelry requires absolute skill and perseverance to create. Our pear shape diamonds all come in brilliant-faceted cuts for the brightest sparkle. | Shop Kobelli Pear High Jewelry.
Approx. Millimeter
Approx. Carat Weight
7 x 4.5
0.5
9 x 5.5
1
9.5 x 6
1.25
10 x 6.5
1.5
11 x 7
2
12 x 7.5
2.5
13 x 8
3
13.5 x 8.5
3.5
14.5 x 9
4
15 x 7
4.5
15.5 x 9.5
5


Marquise

Elegant and rare, marquise cuts hold an air of grandiose extravagance. The slender shape elongates the hand and beautifully carries itself with a romantic flair. | Shop the Kobelli Marquise Collection.
Approx. Millimeter
Approx. Carat Weight
8 x 4
0.5
10.5 x 5.5
1
11.5 x 7
1.25
11.7 x 6
1.5
13 x 6.5
2
14 x 7
2.5
15 x 7.5
3
16 x 8
3.5
16.5 x 8.3
4
17.5 x 6.5
4.5
17.7 x 9
5


Asscher

Asscher cuts are among the most rare shapes on the market and make for a truly unique piece.

The hall of mirrors effect can be seen by looking into this mesmerizing stone, reminiscent of a lifetime of memories. | Shop the Kobelli Asscher Collection.
Approx. Millimeter
Approx. Carat Weight
4.4
0.5
5.5
1
6
1.25
6.3
1.5
7
2
7.5
2.5
8
3
8.3
3.5
8.6
4
9
4.5
9.7
5


Heart

The perfect piece for your sweetheart. Show your love with a classic heart shape. | Shop Kobelli's Heart Shaped Diamonds.
Approx. Millimeter
Approx. Carat Weight
5.5 x 5
0.5
7 x 6
1
7.6 x 6.5
1.25
8 x 7
1.5
9 x 8
2
9.5 x 8.5
2.5
10 x 9
3
10.5 x 9.5
3.5
11 x 10
4
11.5 x 7.5
4.5
12 x 10.5
5