Otto Berg's 5″ diameter optical quartz piece inset with three threaded mounting points, with tapered edges, measuring 1″ thick. The piece is housed in a blue cardboard box, annotated by Berg: "This is optical quartz—an experiment I flew on Von Braun's Jupiter Rocket, 1963." Whether this is the actual flown piece, or a representative example/flight spare, is not clear. In overall very good to fine condition.
From the collection of Dr. Otto Berg.
