Calcium oxide (CaO) or quicklime can be classified as either high calcium or dolomitic. High calcium quicklime has typically >97% CaO with magnesium oxide (MgO) levels less than 3%. At MLC, our high calcium oxide (CaO) content is a result of our 98.5% pure calcium carbonate (limestone). Dolomitic quicklime generally contains >40% MgO along with the calcium oxide. See our website under the “Products” tab to view more information.

Calcium hydroxide {Ca(OH)₂}, or hydrated lime, is a refined product. Calcium oxide is stoichiometrically reacted with water in a controlled process to form a calcium hydroxide product that has the consistency of a fine white powder containing less than 2% residual moisture. There are two major types of hydrated lime – Type N and Type S. Type S hydrated lime is mainly used in the building construction industry. Our hydrated lime portfolio is centered on Type N (Normal) Hydrated Lime. See our website under the “Products” tab to view more information.

Ground calcium carbonate or limestone occurs naturally and is commonly called chalk or marble. MLC ground calcium carbonate is mined from one of the purest limestone deposits in the world with an average purity of 98.5% CaCO₃. See our website under the “Products” tab to view more information.

Other calcium products is a group of limestone derivatives co-products that have not been previously discussed. Some typical materials are hydration process tailings (Code H), lime kiln dust (Code L), and limestone screenings. See our website under the “Products” tab to view more information.

Quicklime and hydrated lime should be treated as any other chemical and users should refer to Material Safety Data Sheet (MSDS) prior to use.

Lime needs to be stored in silos or at a minimum under roof in dry areas. Since quicklime products are hydroscopic it can react with the moisture in the air.

In general, lime when transported via rail or motor is not considered hazardous. Please refer to the US DOT requirements for air shipments.