Diameter of 1 carat round diamond?

[kkcat]

Good afternoon all,

I am looking at the diamond, great ASET images, specifications look great too.
But, the diameter seems to be small for 1 carat?
What is a typical diameter for an ideal cut 1 c round diamond ?

Table 55%
Depth 62.2%
Crown angle 34.4
Pavilion 41.0

Diameter 6.45mm

Thank you!!!

 

[kkcat]

Hm. That's weird. I see that someone replied to my thread. But when I open it to view the reply, it is not there.
Is this a tech glitch?

 

[John P]

Good afternoon all,

I am looking at the diamond, great ASET images, specifications look great too.
But, the diameter seems to be small for 1 carat?
What is a typical diameter for an ideal cut 1 c round diamond ?

Table 55%
Depth 62.2%
Crown angle 34.4
Pavilion 41.0

Diameter 6.45mm

Thank you!!!

Diameter is a function of all proportions working together. A single set of nice proportions can vary somewhat in spread, diamond to diamond, depending on girdle thickness.

As an example, three diamonds could all have modern Tolkowsky proportions (56T 34.5CA 40.75PA), but their spread will vary depending on girdle thickness. One with a slightly thick girdle, creating 62.5%D, may spread 6.38mm. Another with a medium girdle and 61.5%D, may spread 6.45mm. Yet another with a thin girdle and 60.5%D may spread 6.50mm.

The most important component influencing size-appearance in daily viewing is cut which promotes edge-to-edge light performance. Even a spready diamond will go dark at the edges, and appear smaller in normal/low light conditions, if it doesn't have top cut quality.

When you have high performing diamonds, returning light all the way to the edge, the differences in the 1ct scenarios described above are extremely slight, especially when the diamond is set.

 

[kkcat]

Thank you John! That explains it well!