20 Ton Telescope Mirror Worth Quarter Of A Million Arrives For Polishing In Newcastle: The largest piece of glass ever imported into the United Kingdom, a 20 ton telescope Mirror, has arrived at the Grubb Parsone Works at Newcastle Upon Tyne for an eighteen month grinding and polishing operation. The new 155.5 inch mirror made of a zero-expansion glass-ceramic material called "Cer~~~~ Vit" developed by Owens Illinois U.S.A. was cast in Toledo, Ohio, in April this year. It will be installed in a telescope being jointly developed by the British Science Research Council and Australian Department of Education and Science at Siding Spring Mountain, New South Wales. Photo shows The Mirror blank is inspected before grinding and polishing starts at the Grubb Parsone Works at New Castle today.
Photo measures 10 x 8 inches.
Photo is dated 12-10-1969.
Photo back: