Other two wizards

This question might have two parts. I know three of the wizards. There's Gandalf the Grey, Saruman the White, and Radagast the Brown.

Question number one: Did Tolkien ever mention the other two wizards in any of his writings?

Question number two: If he didn't, what colors do you think might be ascribed to them?

Grey, white, and brown are all very neutral tones. Does that leave us with Bill the Teal, and Frank the Cream? Or are they the "bright" ones of the lot, e.g., Biff the Fuscia and Gerald the International Day-glo Orange?

Seriously, I pick green and blue, earth and sky colors. Then again, this all might be moot if he has identified them in some other writing.