light concrete blocks
Does "light concrete blocks" in the following context mean '"small and not heavy concrete blocks"? I think it refers to the fact that small not-heavy blocks placed beside each other constitute a big heavy block, as this memorial is a big black cubic form.
The American Sol LeWitt’s Black Form: Dedicated to the Missing Jews appeared first in Münster, Germany, in 1985 and, after demolition and rebuilding, in Hamburg in 1987. The black cuboid stands in front of and parallel to the impressive Altona Town Hall at one end of the Platz der Republik. The black-painted structure, 5.5 x 2 x 2 metres, consists of light concrete blocks built on a foundation. The artist wanted no inscription. Two plaques on either side explain the piece’s origin in the history of Altona’s Jewish community.