6" spherical mirror with 2" hole

From a spectrograph or possibly a small telescope. Box is labelled '6" spherical mirror with 2" hole/ Fragile/ Vacuum coatings Group/ From: D. Jackson (RGO)/ - 62cm focal length/ For: Dr A G Spencer'.

Object Details

ID: ZBA0714
Collection: Astronomical and navigational instruments
Type: 6" spherical mirror with 2" hole
Display location: Not on display
Creator: Unknown
Date made: Unknown
Credit: National Maritime Museum, Greenwich, London
Measurements: Overall: 25 mm; Diameter: 151 mm