In Borg (ed.) 1999. The Language of Color in the Mediterranean. 166-174.
The nomadic Berbers have a set of abstract color verbs (language: Tuareg], and does not use color adjectives per se, but participles from the verbs [167-8]. [This seems similar to Pliny's use of rubeo, rubens. I wonder if it isn't some dialectal difference in P due to his Spanish background.]
Berbers don't clearly distinguish green and blue .