Asha is singly refractive, just like diamond.
Moissanite is doubly refractive, which is why it will look blurry rather than crisp when viewed at close quarters.
More details:
A gem quality diamond will exhibit a crisp, clear look to it.
This is because its internal crystal structure is face-centered-cubic. By comparison, Moissanite is hexagonal...which means that it will not handle light the way a diamond does, and creates what is termed "bi-refringance".
Basically, light waves are split inside the crystal and their velocity becomes unequal...thus things appear doubled in appearance. The end result is that Moissanite does not look like a diamond when examined closely. Instead, it will appear fuzzy or blurry to the eye.
By comparison, Asha® perfectly mimics the diamonds crystal structure (face-centered-cubic) resulting in a virtually identical look as fine diamond.
