Chris – I found an entry of Skull, it was written for a telephone type dictionary – one could ring up to hear what it was. I have put it now in the Dictionary on the site, but as I haven’t yet got up to the SK’s in revising, so it needs extra work.
The light blue suggests some connection with the heavenly wisdom – i.e. things you can contact and understand that are beyond the physical senses.
I guess it is important to you, but as usual it is your own associations that might take you ‘higher’.
Tony