Top from the mid-10th century in a diamond-shaped block.
I have a few more diamond-shaped blocks in my files.
But these don't seem to have names and I haven't found them
published any where.
See the first post on diamond-shaped blocks here:
Top from about 1875-1900
You could look at these two as variations on the triangular block Sugar Loaf
See more about triangular blocks here.
Most triangular blocks could be doubled to make a diamond.
From the 1940s-1960s
From the 1930s in an online auction.
Sandi Klop at American Jane with a repro in her
Bread & Butter fabric collection.
Dreaming of Diamonds
Lissa Alexander's recent take on the diamond-shaped
block filled with diamonds.
This old pattern seems one of a kind.
Late 19th century (?) top
Until you find two of a kind.
The vintage quilt above is labeled Quilt Index.
Did it start out to be one of these?
Or just an odd relation.
Diamond-shaped blocks enjoyed a short and minor popularity for what we call
contained crazy quilts.
From the Nebraska History site
From the Tennessee Project and the Quilt Index
Collection: Metropolitan Museum of Art
This sampler with square patchwork cut into diamond shapes
may actually be one of a kind.
On the topic of one of a kind---the Connecticut
Project found this very strange diamond quilt,
alternating pieced and appliqued blocks (I think.)
Or maybe it's a fussy cut paisley print.
A unique personal vision.