- Joined
- Aug 4, 2008
- Messages
- 14,681
another factor in fire is dwell time or how long it lasts.
For example many crushed ice stones when the stone is moved in a typical fashion you never see the fire flashes because they do not last long enough to register.
Turn it very very very slowly and you can see them.
on the other side of the range you have the long thin VF's in the center part of emerald cuts that have a very long dwell time for both the on and off state which in many cases can be so long that it doesn't even register as a sparkle. This is more common in large tabled stones with shallow crowns and leads to the name glassy.
When designing a diamond I take into account VF: size, shape, intensity and dwell time for both colored and white light.
If I can make to adjacent VF's out of phase with each other all the better.
That will make them each look brighter because of contrast brilliance if they switch phases at different times.
For example many crushed ice stones when the stone is moved in a typical fashion you never see the fire flashes because they do not last long enough to register.
Turn it very very very slowly and you can see them.
on the other side of the range you have the long thin VF's in the center part of emerald cuts that have a very long dwell time for both the on and off state which in many cases can be so long that it doesn't even register as a sparkle. This is more common in large tabled stones with shallow crowns and leads to the name glassy.
When designing a diamond I take into account VF: size, shape, intensity and dwell time for both colored and white light.
If I can make to adjacent VF's out of phase with each other all the better.
That will make them each look brighter because of contrast brilliance if they switch phases at different times.
300x240.png)