Lighting guru James Turrell used to have two Gramercy Park apartments. And now he has but a-one. 6sqft first caught sight of the news that "Alchemy: A James Turrell Space"a unit he combined at 26 Gramercy Park South that comes with with one bedroom, two bathrooms, a coveted key to the park, and some seriously sleek design chopshas sold for $2.1 million. He listed it in August for $2.2 million. Want a crack at another place the Guggenheim-clogging artist owns? He's got a $2.85 million apartment nearby on the market.