This is a really fantastic Ben Zuckerman suit from the 1960's. It is a dark grey wool lined in sunshine yellow silk and trimmed in astrakhan, which is the fur of very young Karakul sheep.
The really striking thing about this outfit is the wonderful silk blouse. The blouse is sleeveless and has a 'barrister' collar. You can see that it fastens with press studs so that the clean line of the front of the blouse is not interrupted with buttons. The jacket has matching cuffs in the same yellow silk so it looks like the blouse is long sleeved when the jacket is on.

Photos courtesy of Sorpha.