The invention generally provides gypsum-containing slurries including
stucco, a hydroxyethylated starch, naphthalenesulfonate dispersant, and
sodium trimetaphosphate. The naphthalenesulfonate dispersant is present
in an amount of about 0.1%-3.0% by weight based on the weight of dry
stucco. The hydroxyethylated starch is present in an amount of from about
0.5% by weight to about 10% by weight based on the weight of dry stucco
in the formulation. The sodium trimetaphosphate is present in an amount
of about 0.1%-0.4% by weight based on the weight of dry stucco. Other
slurry additives can include accelerators, binders, paper fiber, glass
fiber, and other known ingredients. The invention also comprises the
gypsum-containing products made with such slurries, for example,
lightweight gypsum wallboard, and a method of making lightweight gypsum
wallboard.