As was explained when the crystal ball was presented as 'Sphere No. 5', although it had been tentatively ascribed to the seventeenth century, its material had not been positively identified. The responsibility of appearing at the scholarly event in Venice meant that any doubts about the composition of the ball needed to be confronted, so it has recently been taken to the mineralogy department of the University Museum of Natural History for examination. The result of microscopical analysis undertaken is that alignments visible in the structure indicated that the ball is 'very probably' made of rock crystal.

The crystal ball can travel to Venice, where it will be on display at the Institute from the 28th April to the 24th May with its credentials intact. There it will join material from such celebrated collections as the Tresoro di San Marco, Venice, and the Opificio delle Pietre Dure, Florence. It will be the first time the Institute has borrowed material from a museum in the United Kingdom.