“Ideal cut” is a term often used when describing diamonds, but what about “fine cut”? Let’s see what “ideal cut” and “fine cut” mean, and find out what the difference is between these two diamond cuts.
How Diamond Cuts Are Classified
The term “diamond cut” refers to the shape and proportions of a polished stone.
The cut of a round diamond (which is the most popular diamond shape) is evaluated according to how close its measurements are to the so-called “ideal standard.”
This standard is simply a set of proportions that have been found to maximize the brilliance and sparkle of a diamond.
There are several ideal standards for diamond cut, and they are all based on research into the way diamonds reflect and bend light.
Although there are differences between these standards, the variations are not dramatic.
What Is Ideal Cut?
The term “ideal cut” generally refers to a diamond cut whose proportions conform to the ideal standard.
When this term is used in North America, ideal cut usually refers to the American Standard for diamond proportions.
This ideal cut was created in 1919 and has been used to evaluate diamonds since then.
In diamond quality grading, the cut of a stone is assigned a grade according to how close the diamond’s proportions are to the ideal cut.
In the U.S., one of the most commonly used grading scales for round diamond cuts is that of the G.I.A. (Gemological Institute of America), which assigns the following cut grades: Excellent, Very Good, Good, Fair, and Poor.
What Is Fine Cut?
The name “fine cut” is usually used to refer to the so-called Practical Fine Cut, which is a standard that was created in Germany in 1939. The fine cut benchmark is currently used in Europe.
So, as it turns out, the terms “fine cut” and “ideal cut” have the same meaning, although they refer to different standards used in different parts of the world.
What Is the Difference Between Ideal Cut and Fine Cut?
Although the American ideal cut and the European fine cut both refer to diamond proportions that maximize brilliance, these two standards differ slightly in the ideal measurements they recommend.
Here are the biggest differences:
A diamond shaped according to the American ideal standard should have a taller crown than that of a fine-cut diamond. (The crown is the top part of a round diamond and is separated from the bottom part by the stone’s edge, or the girdle.)
The American Standard recommends that diamond crown height be 16.2% of the diameter of the girdle, while the fine cut standard stipulates 14.4%.
The table is the flat top of a round diamond, and its diameter is also measured as a percentage of the girdle’s diameter.
The American Standard says that the table should have a diameter that is 53% of that of the girdle.
The proportion recommended for this measure by the fine cut standard is 56%.
There are other differences between the ideal cut and the fine cut, but they are insignificant.
As you can see, these two cuts are pretty similar, and it is unlikely that you would be able to spot a difference between an ideal- and a fine-cut diamond in terms of brilliance.