Thanks Nap! Most kind of you - I really enjoyed this bust.
The leather jacket was straightforward, if time-consuming. I undercoated with a Burnt Umber acrylic, then applied inital shading with Burnt Umber oils and highlighted with Burnt Sienna. In the second round, I left the shadows pretty much as they were. For the second set of high lights, I added a tiny bit of White to the Burnt Sienna to make a slightly orangey tone, then started stippling tiny dots over the highlight areas (this is the time-consuming part). I then added a bit more White to the Burnt Sienna and stippled it just on the highest highlight areas and along seams and edges.
Thanks again for the bust and the kind comments
Cheers,
Brian