More than one experimental rinse tested on Sacagawea dollar coin in year 2000

I have this almost white $1 Sacagawea coin (right side of photo) that I've been researching. At first I thought it might be an error Sacagawea coin that was stamped on a Susan B Anthony planchet Then I thought, perhaps it is just a worn 2000-P Sacajawea. But there is no more wear on its devices than that what appears on any high grade errorless Sacagawea. I have not ruled out a counterfeit, but I found a more plausible explanation in the 4 year discussion on Anti-tarnishing rinse experimentation at the Philadelphia and Denver Mints. The "10" or so 2000-P (I'm not referring to the acknowledged larger number of 2001-P's) experimental Sacagawea coins have been labeled as greenish brown, brown or chocolate in color. But who's to say only one or two experimental trials were run at the close of 2000. Couldn't my Sacagawea be the result of one more anti-tarnish rinse experiment? Why not? Anyone capable of giving me a better explanation?