Ernesto Pujol, a New York-based artist, is coordinating a public group performance, "Speaking in Silence," at 12 sites around Honolulu from sunrise to sunset on Saturday. He is collaborating with 19 local artists who will be dressed in red and perform — either alone or in pairs. Locations include Aloha Tower, Iolani Palace and Waikiki Natatorium War Memorial. More sites can be found at www.honoluluacademy.org. The performance is being held in conjunction with an exhibit "Ernesto Pujol: Walking Ground," on view at The Contemporary  Museum through Oct. 3. For more information, call 532-8700.