It takes a master collector to start a thread like this.

Let me lend a hand.
These have all been confirmed as being done by Chris, ususally via emails from Anne. The first is a Small P UG, with a purple anodized thumstud. Chris seems to like making circles, and the motif shows up often is his work.
This large P has a silver thumbstud and single large circle that changes as the light shifts. A very cool effect. It is accompanied by Regular #188, with graphics also done by Chris. FWIW, #188 has the earliest cabochon that I've yet seen. It's amethyst.
Here is #172, with an intesting lens effect.
This is #19, which made it's way back from across the pond a couple of years ago. It has what is probably my favorite graphic. The scene almost looks like a ship getting tossed in a storm. (photo by Mr. Ashton)
#169 Reg really has a different look to it, but again it was done by Chris.
And this UG is from 1997. I wasn't sure about the graphics, but Chris (via Anne) confirmed he did this one as well. This has been my "on again, off again" EDC for the last few years whenever I have hankering for BG42.
Here's a group shot. Since this was taken, the small Damascus has seen couple more owners, ending up with Lone_Wolfe above