Why so much color change in synthesis of triphenylmethanol? In lab today, I prepared a solution of Grignard reagent (phenylmagnesiumbromide) in anhydrous ether. I then added a solution of diphenylmethanone in anhydrous ether (AKA benzophenone) to the Grignard reagent and observed a brilliant array of color change. 

Immedietely when the first drops of the benzophenone were added to the cloudy grayish grignard mixture (grey color due to impurities in starting magnesium), the reaction turned a dark purple before quickly changing to a crimson red, before once again changing to a bright pink. As more benzophenone was added, the reaction mixture changed, once more, to a milky white color and promptly hardened.

I understand the white final color and hardness is due to formation of my intended product: triphenylmethoxide magnesium salt...

But WHAT in the world was happening in that reaction with all those fantastic color changes?
It sounds like you might have generated a species with this structural moiety:
 

This can happen if your solution was concentrated enough or the boiling of your ether was vigorous, so the local overheating caused the formation of $\ce{MgO}$, the guy above, and $\ce{Br-}$, which gives a very distinct bright red-pink color, which is VERY bright and only requires a bit of the side product to form. Though this carbocation is kinda stable, it will find the $\ce{Br-}$ in the solution and form triphenylmethylbromide as a minute impurity.