Antimony Metal for Lead Alloys and Industry

Chemically, antimony is classed as a metalloid: it sits in group 15 of the periodic table and has some properties of metals and some of non-metals. In the trade it is handled as a minor metal and sold as ingots, lumps or broken cakes, typically with a bright, crystalline fracture.

It is a poor conductor of heat and electricity for a metal, very brittle, and unusual in one respect: it expands slightly as it solidifies. That was useful in the old type metal used for printing, where the expansion pressed the alloy into every corner of the mould.

Pure lead is so soft that a battery grid made from it would sag and a bullet would deform in the barrel. A few percent of antimony changes that. It forms a hard second phase in the lead, raising hardness, tensile strength and resistance to creep, and it lowers the melting point slightly and improves casting fluidity.

The resulting hard or antimonial lead is used for lead-acid battery grids and terminals, cable sheathing, ammunition and shot, ballast and weights that must hold their shape, and chemical lead parts that need stiffness. In India, lead-antimony alloys are covered by IS 1654. See our lead sheet page for where soft and hard lead are used.

Older flooded lead-acid batteries used lead-antimony grids throughout. Antimony makes strong, easily cast grids that tolerate deep cycling, but it also increases water loss and self-discharge. Maintenance-free automotive batteries moved largely to lead-calcium grids for that reason. Antimonial grids remain common in deep-cycle, traction and many industrial batteries, and low-antimony alloys are used in hybrid designs, so battery makers are still a steady market for antimony.

If you cast battery parts or alloy your own lead, our lead ingots and antimony can be quoted together.

Battery recyclers, who recover lead from scrap batteries, also adjust antimony up or down when refining the recovered metal into soft lead or antimonial alloys for reuse.

• Flame retardants: antimony trioxide works with halogenated additives in plastics, cable compounds, textiles and coatings; this is the largest use worldwide, roughly half of consumption in 2023
• Solar and specialty glass: antimony compounds are used as fining agents, and photovoltaic glass took about a fifth of consumption in 2023
• Bearing alloys: tin-based and lead-based white metals contain antimony to form hard bearing crystals
• Ammunition and defence: hardening bullet lead and other military uses
• Semiconductors and electronics: high-purity antimony for compounds such as indium antimonide

China mined about 48 % of the world's antimony in 2023, according to USGS figures, and supplies the large majority of antimony trioxide. In August 2024 China announced export licensing for antimony products, effective 15 September 2024. Prices had already reached record levels that summer, and the controls added to the uncertainty.

For Indian users, that means quotes may be valid for a shorter period than you are used to and availability can change at short notice. We confirm price and quantity at the time of enquiry rather than holding long-dated offers.

Antimony metal is traded by purity, with 99.65 % Sb a common commercial grade and higher purities, around 99.9 %, sold for more demanding uses. IS 211 is the Indian standard for antimony ingot. Tell us the purity, the form (ingot, lump or crushed), the quantity and the end use, and we will confirm what is available. Every supply carries a test certificate through a Govt. recognised test house.

Antimony and its compounds are toxic if swallowed or inhaled as dust or fume. Crush and melt it with extraction and dust masks, and keep it away from food areas. Antimony trioxide in particular needs careful dust control.