Maccle Diamonds

I ws reviewing email this morning and came across a term I was unfamiliar with and couldn’t find on wikipedia (sorry about the limited research. What is a maccle diamond. There were pictures of small triangular diamonds. Can anyone provide history of term, origin of diamonds, etc. I don’t use stones much in my work, but have an academic interest in new things.
Thanks

James, you asked “what is a macle diamond?”

Macles are diamond crystals that are flattened and triangular in shape with two crystals sharing a common face.

These twinned crystals are typically fashioned into heart, pear and triangle shapes to make efficient use of the rough.

Originally the triangles were given a tabular or step cut,

but in the 1950’s cutters began to experiment with new faceting patterns to increase their brilliance.

The Royal Asscher Diamond Company produced a brilliant-cut triangle with arching sides in 1960 and named it the trilliant.

In 1962 Irving and Milton Meyer created an American version with straight sides and called it the American trilliant.

Renee Newman

Author of the Diamond Handbook

www.reneenewman.com/handbook.htm

Thanks for your information.

Jim