It turned out to be doeskin and for an XJ40
My computer chair had been falling apart for a while now, most of the seat and foam rubber has disintegrated so I decided to marry the Jag seat to the office chair base. I removed the seat mechanism along with all the electrics and any unwanted parts, then modified the swivel chair by welding on angle iron. The base construction is shown below.

The project was quite easy and a great success, so I'm now typing this in supreme comfort with that lovely leather aroma all around



