The Shining Trapezohedron

Of the Shining Trapezohedron he speaks often, calling it a window on all time and space, and tracing its history from the days it was fashioned on dark Yuggoth, before ever the Old Ones brought it to earth. It was treasured and placed in its curious box by the crinoid things of Antarctica, salvaged from their ruins by the serpent-men of Valusia, and peered at aeons later in Lemuria by the first human beings. It crossed strange lands and stranger seas, and sank with Atlantis before a Minoan fisher meshed it in his net and sold it to swarthy merchants from nighted Khem. The Pharaoh Nephren-Ka built around it a temple with a windowless crypt, and did that which caused his name to be stricken from all monuments and records. Then it slept in the ruins of that evil fane which the priests and the new Pharaoh destroyed, till the delver’s spade once more brought it forth to curse mankind.

 - H.P. Lovecraft, "The Haunter of the Dark"

The Real Schlitzie brings us this recreation of the accursed Shining Trapezohedron.  For a doom-bringing alien artifact it looks pretty cool.