23 x 10 x 9 cm
9" x 4" x 3.5"

Optical glass prisms in velvet lined mahogany box, white base.

One of a series of 9 Crystal Clusters, works using periscope prisms made for 2nd WW Centurion tanks.

From these, I created a number of different shapes, each made of two prisms, which could be put together like a jigsaw puzzle to fit into a square, rectangular or rhomboid velvet-lined box.