No text, but a visual code

[ReneZ]

If the Voynich manuscript has been modelled upon the Lapidary of Alfonso,

Let's not forget that there are numerous manuscripts dedicated to the various properties of each degree of the zodiac. The Lapidary of Alfonso is well known because it is beautifully illustrated and used to belong to a king, but there are many other illustrated manuscripts and even more non-illustrated ones. 

Not all illustrated manuscripts use circular diagrams, but they show the same type of information.
You are not allowed to view links. Register or Login to view.  is a well-known example of the former, and You are not allowed to view links. Register or Login to view.  of the latter.

More important than these examples is that the theory behind this can be traced back many centuries and across late medieval Europe.
There are many ways how something similar could have ended up in the Voynich MS (if indeed this is the case). 
I find that idea very attractive, but of course we don't know yet.