A contact lens blocking composition with desirable melt properties can comprise a water soluble polymer such as a polyalkylpolyimine combined with an absorbent disintegrant or with a filler such as a highly soluble salt composition or both. The blocking composition can be readily removed from a shaped contact lens after machining and from the mandrel or other tool used in shaping the lens. The blocking composition is readily removed using an aqueous wash, aqueous washing solutions or ultrasonic cleaning procedures.