The clock face is a piece of spalted maple that has been cut round and machined thin enough to let the LEDs shine through, then finished using lacquer, then buffed.
The rings are centered with the smallest (12 LEDs) at the center indicating hours, the medium-sized (24 LEDs) indicating the minutes (roughly, given there are 24 LEDs only) and the outer ring (60 LEDs) indicating the seconds.
The electronics are made from spare parts I had: an arduino nano for the running the code and driving the neopixel rings, and a DS3231 real-time-clock to keep track of time.
I love the look of spalted maple, and I really like the idea of making it transparently thin. Looking forward to pictures.