Ancient Egyptians lined their eyes with a black cosmetic called 'kohl' over 5,000 years ago. That eyeliner was antimony sulfide (Sb₂S₃). Antimony became one of the first elements humans ever used — long before anyone understood chemistry.
Today antimony hides wherever fire protection is needed. Antimony oxide (Sb₂O₃) is the leading flame-retardant additive for plastics, textiles, and electronics. Billions of devices — from phones to aircraft — are shielded from fire thanks to this metalloid.
Antimony has a rare property: it expands when it solidifies, just like water. This makes it perfect for printing alloys and bearings — the metal fills a mold exactly, with no shrinkage.
Antimony is also a component of lead-acid batteries: 3–6% antimony increases lead's hardness and extends battery life to 5–7 years. Every car battery contains a small amount of antimony.
Antimony and its compounds are classified as hazardous. Dust and fumes of its oxide irritate the respiratory tract, skin, and eyes. Prolonged exposure leads to 'antimonosis' — lung accumulation resulting in pneumoconiosis. Stibine (SbH₃) is a lethally toxic gas, dangerous even at trace concentrations. The occupational exposure limit is 0.5 mg/m³. Exhaust ventilation, a respirator, and safety goggles are mandatory.
Egyptians used antimony sulfide as eyeliner ('kohl') over 5,000 years ago. Cleopatra wore it too.
Antimony oxide (Sb₂O₃) protects billions of electronic devices, fabrics, and plastics from fire — from phones to aircraft.
Antimony is one of the few elements that expands when it solidifies (like water). That makes it ideal for precision casting.
The symbol Sb comes from Latin 'stibium,' while 'antimony' derives from Greek 'anti-monos' (not alone), because it's rarely found in pure form.
Stibine (SbH₃) is an extraordinarily poisonous gas — even more toxic than arsine. It forms when antimony contacts acids.
| Isotope | Mass (u) | Abundance | Half-life | Decay |
|---|---|---|---|---|
121Sb | 120.903816 | 57.21% | stable | — |
123Sb | 122.904214 | 42.79% | stable | — |
Known since antiquity