Cast concrete columnar pedestal with square top and base. Top and base measure 12 x 12 inches.  In addition to a planted container, this vintage pedestal would be apropos for a copper or bronze Armillary:
https://detroitgardenworks.com/?s=armillary&submit=
or other garden ornament. It is also beautiful enough to stand alone as an architectural element for the garden or an entrance.
12 x 12 x 28″