Wollastonite

Description

Wollastonite · CAS 13983-17-0 · Ca.Si.O3. UNII T57XQ6TH2A. Melting Point: 2804 °F (NIOSH, 2024); Vapor Pressure: 0 mmHg (approx) (NIOSH, 2024).

Identification

CAS Registry Number	13983-17-0
PubChem CID	26370
Molecular formula	Ca.Si.O3
IUPAC name	calcium dioxido(oxo)silane
UNII (FDA)	T57XQ6TH2A

Computed Descriptors

Molecular Weight	116.16
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	3
Rotatable Bond Count	0
Exact Mass	115.9242612
Monoisotopic Mass	115.9242612
Topological Polar Surface Area	63.2
Heavy Atom Count	5
Formal Charge	0
Complexity	18.8

Physical & Chemical Properties

Melting Point	2804 °F (NIOSH, 2024)
Vapor Pressure	0 mmHg (approx) (NIOSH, 2024)

Physical description & handling notes

• Wollastonite appears as white or slightly cream-colored powder. pH (aqueous slurry) 8.0 to 10.0. (NTP, 1992)
• Dry Powder
• CBI; Dry Powder
• White to cream-colored solid; [CAMEO] A glass-like solid with a color that varies from white to brown, red, gray, and yellow; [Hawley]
• White to brown, red, gray, yellow solid; vitreous to pearly luster
• White monoclinistic crystals

Regulatory Status

Regulatory & Food Contact	FDA Inventory of Food Contact Substances Listed in 21 CFR: FCS CALCIUM METASILICATE
GHS notification summary	86.5% (642 / 742)

GHS Hazard Classification

GHS notification summary	86.5% (642 / 742)
Reported hazard statements	H319 (12.3%), H335 (12.3%)

Documented Uses

• Used in ceramics, welding rod coatings, soil conditioners, silica gels, paper coatings, and fillers for paint, rubber, plastics, cements, and wallboard; [Hawley] Crystalline silica not bound to other minerals is free silica. Silicates are minerals in which silicon and oxygen are combined with other elements. [Rom, p. 364]
• Pulp and Paper Processing [Category: Industry]
• Painting (Pigments, Binders, and Biocides) [Category: Paint]
• Cement Producing [Category: Industry]
• Ceramics making [Category: Hobbies]
• Ceramics; paint extender; welding rod coatings; rubber filler; silica gels; paper coating; filler in plastics, cements, and wallboard; mineral wool; soil conditioner

Synonyms

Aedelforsite; WOLLASTONITE; 13983-17-0; Casiflux; Wollastonite (Ca(SiO3)); Cab-O-lite; Gillebachite; Schalstein; Wollastokup; Bistal; Fuwalip; Rivaite; Vilnite; Tabular spar; Fibernite HG; Vansil W 10

Frequently Asked Questions

What are the CAS number and molecular formula of Wollastonite?

CAS 13983-17-0; molecular formula Ca.Si.O3; molecular weight — g/mol.

What other names is Wollastonite known by?

Aedelforsite, WOLLASTONITE, 13983-17-0, Casiflux, Wollastonite (Ca(SiO3)), Cab-O-lite.

What is the regulatory status of Wollastonite?

Documented regulatory listings: FDA Inventory of Food Contact Substances Listed in 21 CFR: FCS; CALCIUM METASILICATE.

Is Wollastonite classified as hazardous?

86.5% of GHS notifications report no hazard classification (642 of 742).

What are the key physical properties of Wollastonite?

Melting Point: 2804 °F (NIOSH, 2024); Vapor Pressure: 0 mmHg (approx) (NIOSH, 2024).

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.