Uses around 100 MTH-90 (MTX-90) cold cathode trigger tubes in ring counters.
Title is not quite correct due to 3 diodes being used in the power supply but other than that no semiconductors are used for logic or switching. Links to referenced schematic are below
http://www.sgitheach.org.uk/nixie3.html
http://www.sgitheach.org.uk/nixie8.html
http://www.pa3fwm.nl/projects/neonclock2/
