A n By 1 Diamond consists of two lines of n (2 or 3) and two single dancers, forming a diamond formation. See diagrams below.

This is a 3 By 1 Diamond (6 Centers)   Another 3 By 1 Diamond (2 Centers)

Note: The n By 1 Diamond concept is not well defined and seems to be limited to a specific set of calls. Some callers want the dancers in the Line of n to do their part as if the Line of n was Solid. Some callers want the dancers in the Line of n to do their part working Concentric.

From the formation on the left above: 3 By 1 Diamond Circulate 3 By 1 Diamond Flip The Diamond 3 By 1 Diamond Cut The Diamond

From the formation on the right above: 3 By 1 Diamond Circulate 3 By 1 Diamond Reverse Flip The Diamond 3 By 1 Diamond Reverse Cut The Diamond

3 By 1 Diamond Cut The Diamond:     before 3 By 1 Diamond Cut The Diamond   after

Note: When doing a n By 1 Diamond Circulate, be sure to change who has the center hand-hold, just as in a normal Diamond Circulate.