Hi, This cessation would be in 2 stages, the first when Columbia discontinued their production of black WAX cylinders, and the 2nd when they dropped their output of Indestructible (celluloid) cylinders. Both exact dates are in PHP, but I can double-check it. Allen _www.phonobooks.com_ (http://www.phonobooks.com) --------------- In a message dated 2/15/2013 6:19:22 A.M. Eastern Standard Time, [log in to unmask] writes: These list cylinders.Just curious when did Columbia discontinue cylinders? Roger