Asscher Obstruction Testing

[tank007]

What are indicators/how can one tell if an asscher diamond is overreacting to obstruction rather than having normal reaction? Is there a visual way to test this and are step cuts more prone to obstruction considering their steps/mirror like facets than other cuts? What amount of obstruction is acceptable and what's not?

 

[Karl_K]

Look at it then tilt it.
Does it form pleasing patterns face up?
Do the dark areas flash with little tilt?
Repeat at different distances.
Around 15 inches is a very important distance because on your hand it is a very common viewing distance.(1/2 arm length)
Closer than 10 inches can be discounted.

 

[Karl_K]

Because of the very large virtual facets a little obstruction goes a long way.