4C’s or How to Buy a Diamond

Miracle on 47th Street

Be realistic with your expectations.

-Do you have a 3-carat diamond?
– Yes, we do.
– Top-color, ideal cut?
– Yes. What is your budget?
– 500 dollars
– … You are in luck! We have a flawless 3-carat diamond, and it’s only $500!
– You are kidding!!!
– Yeah…. But you started it!

Diamond is the solid form of the element carbon, crystallized in a cubic structure. Diamond can naturally grow deep inside the earth as a mineral, or it can be of synthetic origin. Synthetic diamonds are called lab-grown or man-made diamonds and they are not discussed here.

Diamonds bring happiness. When they don’t, they are worthless. Learning 4Cs is a shortcut to learning diamond’s basics without having to earn a gemological degree. 4Cs is the time-proven system (courtesy of the GIA) that has helped millions of people purchase diamonds.

You get what you pay for when shopping for a diamond, just like everything else in life. However, there is a reason why some seemingly identical diamonds are priced differently. 4C’s is the best method for sorting the differences and making a smart choice.

Color, clarity, cut, and weight can be dialed up and down, just like frequency faders of an equalizer, except the 4Cs’ output is not volume but the price.

Step 1. Select a budget

Color and weight are more important; clarity and cut have a somewhat smaller effect on the price. Determine what two parameters are most important to you:

  • budget and size
  • budget and grade
  • size and grade

A diamond engagement ring indicates a social status but does not determine it. Spending more than you can afford to show off is not smart. There is always a possibility of an upgrade in the future. Without a microscope, most grades cannot be told apart, except by what’s left in your bank account.

Step 2. Pick a grade

For simplicity, the diamond grades can be grouped into four categories:

  • J-K/SI-I is a budget grade (consider lab-grown as well)
  • H-I/ SI1+ is a smart grade (VS1+ for emerald- and Asscher-cuts)
  • F-G/VS+ is a premium grade
  • D-E/VVS+ is a vanity grade


Inclusions are gifts of nature saving us thousands without anyone able to see the difference. According to GIA, any clarity grade above SI2 is eye-clean, invisible to a naked eye without 10x magnification.

In reality, most SI2 and even some SI1 stones inclusions are visible with a naked eye. “Eye-clean” is not a grade but a subjective opinion that depends on the observer’s eyesight, lighting conditions, depth perception, and even mental condition.

Eye-clean SI1 is a sweet spot for choosing a brilliant cut. On the other hand, VS2 is the lowest recommended clarity grade for step-cut emerald and  Asscher diamonds since their reflections do not mask inclusions well.


Diamond color grade is a major factor in a diamond’s price because it reflects how rare the stone is. Completely colorless diamonds are rare but not necessarily the best-looking. Some feel that diamonds utterly void of color have a somewhat unnatural look, similar to cubic zirconia. However, a small amount of a warm tinge can bring a balanced and natural look.

Carat size

Size is measured in carats. People’s desire for a certain carat size is driven by the social pressure to affirm a social status. The carat size alone without a decent color/clarity grade is a waste of a diamond. Most people are willing to sacrifice carat size in favor of a better grade.

A person’s height, body type, or the length of their fingers has nothing to do with a  diamond size. But the ring style and finger size must be considered when targeting a certain carat size.


GIA evaluates the cut grade for round diamonds only. GIA’s excellent cut grade is essential for a round stone to retain its value. GIA Excellent cut grade guarantees that the stone is beautiful and full of life. In the GIA universe, the cut grade for fancy shapes does not exist. Symmetry is the key to fancy-shaped diamond excellence. Excellent or Very Good symmetry is important for modern diamonds but not for antique cuts.

Beauty is in the eye of the beholder

The regret of a junky diamond lingers long after the joy of getting a bargain is forgotten. People enjoyed wearing diamonds centuries before they learned to sort the good ones from the bad ones. Each grade is not a measure of a stone’s beauty but an indication of its relative rarity and value.

A perfectly symmetrical, completely void of color and inclusions diamond is not necessarily superior to a lower grade stone. It is just different but equally beautiful. Subject to personal taste. Roman poet Lucretius once uttered: “One man’s meat is another man’s poison.”

The Fifth C – Craftsmanship

Jeweler’s ability to take advantage of the stone’s unique features to enhance its presentation is crucial. Conversely, poor craftsmanship can reduce even the most beautiful diamond to a dull pebble.

    Your Cart
    Your cart is emptyReturn to Shop
    Diamond prices guide