Nancy said the quilt was first made in 1819 in Virginia and was "an excellent example of the exquisite needlework of the women of the south."
Double Pyramid can be found in Electric Quilt's BlockBase program as #1702 or Double Pyramid!
This is not a complicated block to make. It's all triangles. I didn't make it as a 6" block because the pieces would be so tiny. Each section of the nine patch block would only be 2" finished. That's 16 little triangles in half of a 2" block!
Directions for making an 18" finished block can be found at About.com.
I found this antique quilt being sold at auction at some point. It is dated 1875-1900 and is registered with the Iowa Historical Museum. It's alternated with a square in a square block. I don't know if this was a typical setting or not.