Skip to primary navigationSkip to main contentSkip to footer
CLOSED SATURDAY JULY 4th! Have a safe and happy Independence Day Amercia!
  • Sign InToggle My Account Menu
    Login
    Forgot Password?

    Don’t have an account? Sign up now

  • Make an Appointment
  • Contact Us
  • AppointmentsBook now
  • Financing AvailableLearn More
  • Toggle My Account Menu
    Login
    Forgot Password?

    Don’t have an account? Sign up now

  • Toggle My Wishlist
  • Toggle Shopping Cart Menu
Koerbers Fine Jewelry Inc logo
  • Engagement & Wedding
    FIND YOUR RING
    Engagement RingsWomen's Wedding BandsMen's Wedding BandsShop DiamondsComplete Diamond Rings
    FIND OUT MORE
    Custom Engagement RingsMen's Wedding Band CustomizerDiamond EducationDiamond Upgrade ProgramFinancing Options
    Menu image
    Menu image
  • Jewelry
    ALL JEWELRY
    EarringsNecklaces & PendantsChainsFashion RingsBraceletsCharmsChildren's JewelryMen's JewelryCostume JewelrySale
    MUST HAVE STYLES
    Diamond StudsTennis BraceletsFlexible BraceletsCross Pendants
    DIAMOND JEWELRY
    EarringsNecklaces & PendantsFashion RingsBracelets
    GEMSTONE JEWELRY
    EarringsNecklaces & PendantsFashion RingsBracelets
    SILVER JEWELRY
    ChainsNecklaces & PendantsFashion RingsBracelets
    Menu image
  • Watches
    SHOP WATCHES
    Men'sWomen'sPre-Owned
    LEARN MORE
    Why Buy Pre-OwnedSell or Trade Your Watch
    Menu image
    Menu image
  • Estate Jewelry
    ESTATE JEWELRY
    Shop All Estate JewelryEngagement RingsWedding BandsEarringsFashion RingsBraceletsNecklaces & PendantsSell Your Jewelry
    Menu image
    Menu image
    Menu image
  • Designers
    Ania Haie
    Ariha Jewels
    Benchmark
    Christopher Designs
    Doves Jewelry
    Eriness
    G-Shock
    Gabriel & Co
    Hearts On Fire
    Koerber's Collection
    Le Vian
    Mark Henry
    Memoire
    Monica Rich Kosann
    Seiko
    Shinola
    Shy Creation
    Simon G
    Sloane Street
    Uneek
    Vahan
    Zeghani
    Menu image
  • Permanent Jewelry
  • Services & Custom
    Custom Design
    Jewelry Repair
    Appraisals
    Gold & Jewelry Buying
    Sell or Trade-In Your Watch
    Financing
    Schedule an Appointment
    Menu image
    Menu image
  • About Us
    About Us
    Contact Us
    Meet Our People
    The Koerber Difference
    Upcoming Events
    Our Blog
    Testimonials
    Book an Appointment
    Menu image
    Menu image
  • Sign InToggle My Account Menu
    Login
    Forgot Password?

    Don’t have an account? Sign up now

  • Make an Appointment
  • Contact Us
Koerbers Fine Jewelry Inc logo
Log In
  1. Home
  2. Education
  3. Diamonds

Learn About Diamonds

The Four Cs of Diamonds:
Our Four C's of Diamonds guide can help you decide on the most important factors when shopping for a diamond. The Four C's of diamonds are known as Carat Weight, Cut, Color and Clarity.

Diamond Carat Weight

The word carat derives from the word carob, a Mediterranean seed, which has an extremely consistent weight for measuring. The greater the carat weight, the rarer, and more valuable the diamond becomes. Five metric carats weighs exactly 1 gram.

Some people want the largest diamond possible. If size is a priority, we at Koerbers Fine Jewelry Inc can help you classify the proper cut, color and clarity to fit your budget economically, and fit your jewelry beautifully. Many of our engagement rings can fit diamonds up to five carats or more, but each ring has different size constraints based on its size and the type of setting. Prong settings can be manipulated to fit virtually any size diamond, but tension-set diamonds and bezel set diamonds have more limitations on size.

  • Dime for size comparison
    17.9 MM
  • Search for a Round diamond, 0.10 carat (3.0mm diameter)
    0.10 CT
    (3.0 MM)
  • Search for a Round diamond, 0.15 carat (3.4mm diameter)
    0.15 CT
    (3.4 MM)
  • Search for a Round diamond, 0.20 carat (3.8mm diameter)
    0.20 CT
    (3.8 MM)
  • Search for a Round diamond, 0.25 carat (4.1mm diameter)
    0.25 CT
    (4.1 MM)
  • Search for a Round diamond, 0.5 carat (5.1mm diameter)
    0.5 CT
    (5.1 MM)
  • Search for a Round diamond, 0.75 carat (5.8mm diameter)
    0.75 CT
    (5.8 MM)
  • Search for a Round diamond, 1 carat (6.4mm diameter)
    1.0 CT
    (6.4 MM)
  • Search for a Round diamond, 1.25 carat (6.9mm diameter)
    1.25 CT
    (6.9 MM)
  • Search for a Round diamond, 1.5 carat (7.4mm diameter)
    1.5 CT
    (7.4 MM)
  • Search for a Round diamond, 1.75 carat (7.8mm diameter)
    1.75 CT
    (7.8 MM)
  • Search for a Round diamond, 2 carat (8.1mm diameter)
    2.0 CT
    (8.1 MM)
  • Search for a Round diamond, 2.5 carat (8.8mm diameter)
    2.5 CT
    (8.8 MM)
  • Search for a Round diamond, 3 carat (9.4mm diameter)
    3.0 CT
    (9.4 MM)
  • Search for a Round diamond, 3.5 carat (9.8mm diameter)
    3.5 CT
    (9.8 MM)
  • Search for a Round diamond, 4 carat (10.2mm diameter)
    4.0 CT
    (10.2 MM)
  • Search for a Round diamond, 5 carat (11.0mm diameter)
    5.0 CT
    (11.0 MM)
  • Round diamond, 6 carat (11.8mm diameter)
    6.0 CT
    (11.8 MM)
  • Round diamond, 7 carat (12.4mm diameter)
    7.0 CT
    (12.4 MM)
  • Round diamond, 8 carat (13.0mm diameter)
    8.0 CT
    (13.0 MM)
  • Round diamond, 9 carat (13.5mm diameter)
    9.0 CT
    (13.5 MM)
  • Round diamond, 10 carat (14.0mm diameter)
    10.0 CT
    (14.0 MM)
  • Round diamond, 12.5 carat (14.5mm diameter)
    12.5 CT
    (14.5 MM)
  • Round diamond, 15 carat (16.0mm diameter)
    15.0 CT
    (16.0 MM)

Diamond Cut

The true definition of cut is the quality of the proportions and symmetry of the diamond. Your diamond's proportions make a vast difference on how brightly your diamond shines. An 'ideal cut' diamond is one that allows the maximum amount of light to return through the top of the diamond, which takes into consideration the depth, table size, crown height and angle, girdle thickness and more. Our diamond professionals will be happy to assist you in selecting the best diamond cut.

After a rough diamond is mined, it is evaluated to determine its best possible cut, in order to maintain the maximum clarity, color, and carat weight. The term 'cut' is often confused with diamond 'shape', such as round brilliant or princess cut.

Diamond anatomy

Ideal

This is the rarest cut grade and reflects the most light.

Excellent

This cut grade reflects a high level of craftsmanship and light performance.

Very Good

This cut grade reflects nearly as much light as an Excellent cut grade, but for a lower price.

Good

This cut grade reflects most of the light that enters the diamond, but not as much as a Very Good cut grade.

Fair

This cut grade may appear dull or even glassy, and is very inexpensive.

Poor

This cut grade is not carried by Koerbers Fine Jewelry Inc and is typically not recommended.

Diamond Color

Color is one of the more noticeable attributes of a diamond and has a heavy impact on the price of the stone. Diamonds range from colorless to yellow or light brown, and are sometimes found in a spectrum of fancy colors, including yellow, blue, and even red diamonds. The less color, the rarer the diamond. After 'Z' on the color scale, diamonds become fancy yellow, which cost more because of their rarity.

F
E
D
F color diamond
E color diamond
D color diamond

Colorless

J
I
H
G
J color diamond
I color diamond
H color diamond
G color diamond

Near Colorless

Z-N
M-K
L color diamond
K color diamond

Noticeable Color

Z-N
M-K
J
I
H
G
F
E
D
L color diamond
K color diamond
J color diamond
I color diamond
H color diamond
G color diamond
F color diamond
E color diamond
D color diamond

Noticeable Color

Near Colorless

Colorless

Diamond Clarity

Diamonds are composed of mostly carbon. During the heating process, other elements become trapped inside, giving each diamond its own unique fingerprint. These inclusions help identify the clarity of your diamond. All diamonds are viewed through a 10x magnification lens by diamond graders.

Close up of inclusions in a diamond

(F) Flawless

No inclusions or blemishes are visible to a skilled grader.

(IF) Internally Flawless

No inclusions and only blemishes are visible to a skilled grader.

(VVS1-2) Very Very Slightly Included

Inclusions are difficult for a skilled grader to see.

(VS1-2) Very Slightly Included

Inclusions are clearly visible but can be characterized as minor.

(SI1-3) Slightly Included

Inclusions are noticeable to a skilled grader.

(I1-3) Included

Inclusions are obvious and may affect transparency and brilliance.

Shop Loose Diamonds

Sign up for our newsletter to receive the latest news, exclusive sale previews, and special offers.

Connect With Us
3095 Blackiston Mill Road
New Albany, IN 47150-9536
(812) 945-5959
Store Information
Follow Us
Koerber
Shop With Confidence
  • About Us
  • Testimonials
  • Education
  • Jewelry Guides
  • Services & Repairs
  • Return Policy
  • Visit the rjo website
  • Visit the jbt website
  • Visit the gia website
  • Return Policy
  • Privacy Policy
  • Terms & Conditions
  • Accessibility Statement

© 2026 Koerbers Fine Jewelry Inc. All Rights Reserved.

Powered by: Punchmark

My Cart
You have 0 items in your Cart.
Loading cart items
Loading

Learn how we use cookies in our Privacy Policy or manage cookie preferences.