Tesseract - Symbol for display box?

[joeranger]

I would like to carve a symbol into my wooden display box that has an association with the Tesseract. I don't really understand the Marvel expanded universe but these things seem to overlap.
I thought about the SHIELD logo, but I would like something a little bit more mystical.
What image is most associated with the cube?

 

[breen2057]

you could use some norse imagery like the wall where the red skull finds it in captain america.