Britannica Sources used in this answer

How do lime and magnesia stabilize soda-lime-silica glass?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Observe how a superhydrophobic multifunctional glass surface resists fogging, glare, and self cleans — industrial glass Examining a superhydrophobic glass surface that resists fog and glare and is self-cleaning.

In the production of soda-lime-silica glass, silica serves as the primary glass former, but it requires a flux—typically sodium oxide derived from soda ash—to reduce its high melting point to a manageable level.123

However, adding soda makes the resulting glass easily soluble in water, rendering it impractical for most commercial uses. Lime (calcium oxide) and magnesia act as stabilizing agents that counteract this solubility. By incorporating these alkaline-earth oxides into the glass composition, the material becomes chemically durable and insoluble in water.23

While these stabilizers are essential for durability, manufacturers must balance their concentrations carefully; adding too much lime can cause the glass to become prone to devitrification, where crystalline phases precipitate out during cooling. Consequently, commercial formulations often use a combination of lime and magnesia to achieve the desired balance of workability, chemical resistance, and stability.23