I thought it might be an Italian X block like
X Block: To say or not to sash but that has squares in the center, so not that.
Then the Indian Hatchet came to mind, but it has diagonal seams in the center.
https://www.quilterscache.com/I/IndianHatchetBlock.html, but if you look closely, this does not.
Whatever it is, it is definitely sashed. I'm thinking you could actually make it like an Indian hatchet if you made the side triangular sections first.
Janey - Neat people never make the exciting discoveries I do.
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