Photo caption: "Two dodecahedra and an icosahedron on display in the Rheinisches Landesmuseum Bonn, Germany."
A Roman dodecahedron or Gallo-Roman dodecahedron is a small hollow object made of copper alloy which has been cast into a regular dodecahedral shape: twelve flat pentagonal faces, each face having a circular hole of varying diameter in the middle, the holes connecting to the hollow center. Roman dodecahedra date from the 2nd to 4th centuries AD and their purpose remains unknown. They rarely show signs of wear, and do not have any inscribed numbers or letters.
Oh, yeah the raised noduals at the corners would let you pull the fabric taunt while keeping it elevated from the surface and you can reach your hand through the hole to grab your needle (...wait, could you? How big are these things?)
They're pretty small, turns out.
small enough to poke a needle all the way through, hah! my baseless speculation still holds!