Lighten Object, Mass

Transmutation
Level: Cleric */Oracle * 5, Magus * 5, Sorcerer */Wizard * 5, Summoner * 5
Components: V, M (goose down)
Casting Time: 1 Standard Action
Range: close (25 ft. + 5 ft./2 levels)
Target: multiple objects totaling up to 1 cubic ft./level, no two of which can be more than 30 ft. apart
Duration: 10 minutes/level
Saving Throw: Will negates (object)
Spell Resistance: yes (object)

This spell functions like lighten object, except that it affects a number of objects equal to half your Caster Level.