Magnesium Carbonate Fine Powder (Magnesia)

Premium Magnesium Carbonate (MgCO₃) – High-Purity Light Mag Carb, Ultra-Fine Fluffy White Powder – The Refractory Matte Master & Crawl Creator for Unique Ceramic Surfaces

Elevate your glazes with the distinctive touch of magnesium carbonate (light magnesium carbonate or "mag carb"), the feather-light, high-purity source of MgO renowned for producing silky, buttery mattes, dramatic crawling effects, and controlled opacity. This super-fine, fluffy white powder (typically 99%+ purity) is a favorite among ceramic artists seeking non-traditional, textured, and sophisticated finishes that stand out in any collection.

Why choose our Magnesium Carbonate?

• Excels as a classic matting agent — delivers smooth, velvety matte-to-dry-matte surfaces with a soft, tactile feel, especially prized in dolomite-style or magnesium matte glazes for their buttery, non-reflective elegance at cone 6–10.
• Induces stunning crawling and snakeskin textures — its extreme fineness and high dry shrinkage pull glazes into islands and crackle patterns, creating lichen-like, organic effects in crawl recipes (10–35% additions turn fluid bases into bold, artistic statements).
• Acts as a refractory at lower temperatures — remains partially undissolved to opacify and matte low-fire glazes (cone 04–6), producing bright white, opaque mattes while increasing viscosity and adhesion.
• Lowers thermal expansion — MgO from this source reduces crazing risk dramatically, helping balance high-expansion glazes and prevent cracks on ware.
• Enhances color subtlety — tames vibrant oxides for softer, pastel responses (intense with cobalt for unique purple-violets), while promoting elasticity and smooth, durable surfaces at higher temperatures where it fluxes more actively.
• Versatile in specialty applications — used in bodies for fluxing, in enamels as an electrolyte, and as a precursor in advanced materials; a reliable MgO donor when purity and controlled release matter.

Key Properties at a Glance:

• Chemical formula: MgCO₃
• Appearance: Extremely light, fluffy ultra-fine white powder (light magnesium carbonate form)
• Decomposes during firing to release MgO — the active flux/matting powerhouse — plus CO₂ for clean burnout
• Highly refractory behavior at mid/low temperatures; fluxes more readily at cone 10+ for silky melts
• Contributes high surface tension to the melt, aiding crawl and matte mechanisms

Whether you're crafting silky dolomite-matte stoneware, engineering intentional crawl masterpieces, opacifying low-fire whites, reducing expansion in crackle glazes, or exploring textured, one-of-a-kind surfaces that demand attention, this premium magnesium carbonate delivers dramatic, consistent results with artistic flair.

Handle with appropriate care — its ultra-fine nature creates dust easily (use mask, gloves, ventilation during mixing); store sealed to prevent moisture absorption.

The secret weapon for matte sophistication and bold texture in modern ceramics. Add this lightweight powerhouse to your materials today — unlock buttery mattes, crawling drama, and surfaces that feel as good as they look!

Available in convenient artist quantities and bulk for production studios. Order now and experience the mag carb magic in your next firing!