In 1994 New York City's highest society ladies convened to do good. Nan Kempner, one of the most esteemed members of that coterie, sent out invitations to a charity sale that offered more than the evanescent pleasure of a $10,000 lunch. It gave guests the opportunity to buy a shahtoosh, a shawl that justifies its name, "King of Wool," by reputedly being both light enough to pass through a wedding ring and warm enough to hatch a pigeon's egg. "Shahtooshes are so utterly tightly woven of this wonderful, thin wool," enthuses Kempner. "We started wearing them when people were harassed about wearing fur.