Special coin, is it collectible or valuable?

If you're talking about the coin at the bottom right - that coin has had something done to it outside of the US Mint. Either it was plated or it was exposed to chemicals. Collectors consider it damage. There is no value above face value. The other two Sacagawea dollars are normal D- mint circulation strikes.

http://en.wikipedia.org/wiki/Sacagawea_dollar

United States dollar coin that has been minted every year since 2000, although not released for general circulation from 2002 through 2008 and again from 2012 onward due to its general unpopularity with the public and low business demand for the coin.

http://www.usacoinbook.com/coins/dollars/sacagawea...

While the coin has been minted repeatedly, not in the silver - it is likely that someone has treated it with mercury or plated it to give it that color. Not a valid collectable.