The material below is Open Game Content from a 3PP Source
Lighten Object, Mass
School transmutation; Level cleric 5, sorcerer/wizard 5, summoner 5
Targets multiple objects of 1 cubic ft./level, no two of which can be more than 30 ft. apart
Duration 10 minutes/level
This spell functions like lighten object, except that it affects a number of objects equal to half your caster level.