Ovals w/o Bowtie?

[Ann]

How difficult is it to find Ovals without the dreaded bowtie?

Is there a depth number that one would not exceed or go under - to avoid the bowtie?

I know, you have to look, but any basic guidelines?

 

[beryl]

Ann:
To avoid the typical 'bowtie' in a diamond, the depth of the pavilion should be between 43 and 48% of the girdle WIDTH (ref: 'Faceting Limits', G&G, Fall 1975).
If the cutter tries to make the 'culet' come to a point, the slopes of the end facets will become too shallow. For good results, look for an oval with a wedge-shaped pavilion - a ridge instead of a point.
The azimuths (rotational angles at which the facets are cut) are also important to beauty of an oval-cut stone; this is a factor often misunderstood by cutters.
An article on this (recreated from thread 3 yrs ago in 'DiamondTalk') may appear here soon.

 

[valeria101]

Date: 12/1/2005 2:15:31 AM
Author: beryl

To avoid the typical 'bowtie' in a diamond, the depth of the pavilion should be between 43 and 48% of the girdle WIDTH (ref: 'Faceting Limits', G&G, Fall 1975).

Any chance DC can be used to show these things?

( the question was also posted on the DC thread on FAQ here )


I am looking forward to this, of course.

 

[Serg]

Ann,

To try find oval with split main pavilion facets in min. diameter