Skip to content
glossary/gcc

GCC (ground calcium carbonate)

Also: GCC, ground calcium carbonate, calcium carbonate filler

A paper filler and coating pigment made by grinding limestone. The most-used inorganic additive in paper worldwide.

GCC is mined and ground from natural limestone. It adds opacity, brightness, and printability at lower cost than fiber. Used as a filler (mixed into the sheet furnish, 10 to 30% of mass) and as a coating pigment (applied to the surface, in blade and film coatings).

GCC-filled papers gained ground over PCC-filled grades after mills moved to neutral sizing, which allowed higher GCC loadings without acid degradation.

Related
  • PCC (precipitated calcium carbonate). A synthesized calcium carbonate, chemically identical to GCC but with controlled particle size and shape. Used where optical performance matters.