Sodium nitrate (NaNO3) is also known as Chilean nitrate, and potassium nitrate (KNO3) is also known as nitrite. Their melting temperature is 310-336°C, and they decompose when heated to 400°C. They interact with SiO2 at a lower temperature, thereby speeding up The melting process of glass.

In the process of making glass, some bubbles will appear. The clarifier is used to reduce these bubbles. Commonly used clarifying agents are nitrated salts, namely sodium nitrate.

Sodium nitrate as a decolorizing agent is mainly used to eliminate the undesirable colors brought to the glass by impurities in the raw materials, and make the glass appear colorless and transparent.

There are mainly two types of chemical decolorizers and physical decolorizers. Among them, chemical decolorizers usually decolorize by oxidation, mainly sodium nitrate and potassium nitrate; physical decolorizers make glass colorless by producing complementary colors, mainly manganese dioxide, selenium, cobalt oxide, and bromine oxide.