Answer:

I discovered this wave pattern around 1992 - two years after Mastering Elliott Wave was published. As a result, it is not mentioned in the book.

A NEoWave Diametric is a 7-legged formation (Triangles are 5 legs, Flats and Zigzags are 3) that does NOT involve an x-wave. As a result, instead of a-b-c - X - a-b-c, I had to continue with the alphabet, labeling it a-b-c-d-e-f-g. The distinguishing factor of a Diametric is the similarity of each wave segment in time and complexity to the other six. In Flats and Zigzags, time and complexity differences are extreme between waves-a, b and c. In Triangles less so, in Diametrics time similarity (not time differences) is the norm.

Diametrics occur in two main categories. One in which a period of expansion is evident during waves-a, b, c and d, followed by a period of contraction for waves-e, f and g. The other is the reverse; contraction occurs first during the first four wave segments, followed by expansion for the remaining three. This creates the look of a bowtie for the first series and a diamond shape for the second.