To answer to Keeper :
I've did my DHD for Stargate with a polymer clay, called
"Fimo", oven hardening at 130°F/265°F. Easy to modeling, but rock like after cooking.
You can see more pictures
here and
here.
I used a homemade punch (a "210g" rolled paper...) to get the different trays, the keys have been sculpted with the back of a cutter's blade. The DHD has been cooked in two pieces: the base and the control panel, glued together after hardening. Finally, a red pearl was glued in the middle of the last tray.
The technique to paint marble comes from
TerraGenesis and hieroglyphes were did by hand with Citadel "Dwarf Bronze".
Good luck for your own !