“Four months after spending $7.5 million to buy the Farnsworth House and keep the icon of 20th Century modernism in Illinois, preservationists will open the house for tours Saturday, hoping the public will warm to the cool, steel-and-glass masterwork by architect Ludwig Mies van der Rohe. The 53-year-old house, 58 miles southwest of Chicago, appeared to be in jeopardy until a last-minute surge of donations gave preservation groups the war chest they needed to purchase it on Dec. 12 at a Sotheby’s auction in New York. The groups had feared that a wealthy bidder might move the house out of state.”