Asscher Cut Diamond - Square Emerald Cut Diamond

(“Asscher” Cut)

A Square Emerald cut is a step cut with angled corners and rows of pavilion and crown facets that run parallel to the girdle. “Asscher” is a term often used in the marketplace to describe these square Emerald cuts. The term is derived from the Asscher family name. The Royal Asscher Diamond Company currently produces the “Royal Asscher” cut, which is a patented square step cut with an extra row of facets on top and bottom, a notable high crown, and 74 total facets. http://www.asscher.nl/ Optimal length to width ratio for Square Emerald cuts is .95 to 1.05.

Special Characteristics of the Asscher or Square Emerald Cut Diamond

It is easier to see inclusions in step cuts vs. brilliant cuts. Optimally, a balanced and symmetrical stone with a table % that is smaller than the total depth % is recommended. There are a myriad of combinations that can make for beautiful stones, but guided parameters are now available.

Size Matters

Square Emerald cuts will generally look smaller from the “face up” position than other shapes of the same carat weight. This is a result of their different design and while depth is not strictly tied to spread (as it is with rounds) square emeralds may have greater total depth as a result of optimized angles for light return (good) or pavilion “bulge” (bad).

Basic Asscher Cut Guidelines courtesy of http://www.gemappraisers.com/index.asp

CUT CLASSES	Class 1A	Class 1B	Class 2A	Class 2B	Class 3A	Class 3B	Class 4A	Class 4B
	Ideal cut	Premium cut	International fine trade cut		US domestic average cut		below average
Table %	60-65.5%	59-68%	58-69.5%	57-72%	56-74%	53-76.%	50-78.%	>78% <50%
Crown Height %	12-15.%	11-16%	10-16.5%	9-17.2%	8-18.0%	7-19.5%	6-20.5%	<6% >20.5%
Girdle thickness Word descriptions and percentages.	V. Thin to Sl. Thick (0.4%-4.5%) or Thin to Thick (1%-5.5%)			V.Thin to Thick(0.4%-5.5%)	Very Thin to Very Thick (0.4% to 7.0%)		Extremely thin to Extremely thick (0.0% to >7.0%)
Total Depth %	60-65%			58-69%	57-74%	56-78%	53-80%	>80% <53%
Polish/Symmetry Not a primary determining factor.	Excellent to Good			Good or Fair			Poor to Fair
Square range Length : Width ratios Preferences only	0.95-1.05
Rectangular range Length : Width ratios Preferences only	1.5-1.75			1.49-1.26 1.76-1.99			> Class 3 < Class 3