CI 77220- ▸ Filler & extender: Filler and pigment-extender in plastics, paper, and coatings.
- ▸ Food additive: Dough conditioner, anti-caking, and firming agent.
- ▸ pH & buffering: Acid-neutralizing, buffering, and opacifying additive.
- ▸ Industrial feedstock: Raw material in cement, glass, and lime production.
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
Request SDS →Calcium carbonate (CaCO3, CAS 471-34-1) is a naturally occurring mineral and one of the most widely used industrial chemicals — a white, insoluble powder used as a filler, extender, and source of calcium across construction, plastics, paper, paint, food, and agriculture. It is supplied in two principal forms: ground calcium carbonate (GCC), milled from natural limestone, marble, or chalk, and precipitated calcium carbonate (PCC), synthesized through a controlled chemical process. Both are the same compound; they differ in purity, particle size, brightness, and cost, which is what determines the right grade for a given application.
GCC vs PCC: choosing the right form
Most calcium carbonate volume moves as GCC because it is abundant and cost-effective. PCC is engineered when a formulation needs higher brightness, finer or more uniform particles, or a specific crystal shape. The table below summarizes the practical differences that purchasing and formulation teams weigh.
Applications by industry
Calcium carbonate’s value comes from being an inexpensive, bright, chemically mild mineral that displaces costlier raw materials and neutralizes acid. That combination makes it a staple across most manufacturing sectors.
- Construction & cement: A feedstock for lime and cement and a filler in mortars, sealants, and flooring, where it adds body and reduces binder demand.
- Plastics & polymers: The dominant mineral filler in PVC pipe, profile, and cable, plus polyolefin masterbatch. It cuts resin cost while improving stiffness, dimensional stability, and surface quality — often at high loading levels.
- Paint & coatings: An extender pigment that builds film, controls gloss and rheology, and partially replaces titanium dioxide to lower TiO2 cost while supporting dry-film opacity and scrub resistance.
- Paper: Used both as a furnish filler and a coating pigment to raise brightness, opacity, and smoothness; PCC and fine GCC dominate premium coated grades.
- Rubber & adhesives/sealants: A reinforcing or semi-reinforcing filler and rheology modifier that adds volume and controls flow in caulks and adhesives.
- Food & pharma: A calcium fortificant, anti-caking and firming agent, dough conditioner, and the active in many over-the-counter antacids (this is a factual use, not medical advice). These applications call for USP or FCC grade with documented identity, assay, and impurity limits.
- Agriculture: Ground limestone (“ag lime”) raises soil pH and supplies calcium for crop and pasture management.
- Water treatment: Used to adjust pH and remineralize treated or desalinated water, restoring carbonate hardness and alkalinity.
Frequently Asked Questions
What is calcium carbonate used for?
Calcium carbonate (CaCO3, CAS 471-34-1) is used as a low-cost filler and extender in plastics, paint, paper, rubber, and sealants; as a feedstock for lime and cement; as an acid-neutralizing agent; as ag lime to raise soil pH; for water remineralization; and as a USP/FCC-grade additive in food and pharmaceuticals for calcium fortification, anti-caking, and antacid use.
Is calcium carbonate the same as limestone?
Limestone is a sedimentary rock composed largely of calcium carbonate. Ground calcium carbonate (GCC) is produced by milling limestone, marble, or chalk into a fine powder. So they share the same core chemistry, but commercial calcium carbonate is a refined, size-controlled product rather than raw rock.
What is the difference between GCC and PCC?
GCC (ground) is milled directly from natural limestone, marble, or chalk and is the lower-cost, high-volume form, typically 2-10 microns. PCC (precipitated) is chemically synthesized by calcining limestone to lime, slaking it, and carbonating it with CO2, which allows sub-micron particle sizes, controlled crystal shape, and higher brightness for premium coatings, fine paper, and food/pharma grades.
Is calcium carbonate safe?
Calcium carbonate is a naturally occurring mineral widely used in food, pharmaceutical, and industrial applications, with USP and FCC grades held to defined purity specifications. As with any fine powder, follow the SDS for dust-handling and PPE guidance. This is general product information, not medical or regulatory advice.
What is the difference between technical and USP/FCC calcium carbonate?
All are CaCO3. Technical or industrial grade is controlled for performance properties like particle size and brightness. USP (United States Pharmacopeia) and FCC (Food Chemicals Codex) grades are tested and documented against defined identity, assay, and impurity limits for pharmaceutical and food use. The chemistry is the same; the controls and documentation differ.
Does RawSource supply calcium carbonate in bulk?
Yes. RawSource sources calcium carbonate — GCC and PCC, from technical through USP/FCC grade — in bulk bags, supersacks, and truckload quantities for manufacturers. Send your target grade, particle size, and volume against CAS 471-34-1 for a quote on pack sizes, lead time, and freight.
Need calcium carbonate at production volume? RawSource sources GCC and PCC across the full grade range — technical, food (FCC), and pharmaceutical (USP) — in bulk packaging direct to manufacturers. Request a bulk quote against CAS 471-34-1 with your grade and volume.