Bright red fireworks and signal flares at sea — that's strontium. Its compounds burn with an intense red flame visible from 30 km away. It was named after the Scottish village of Strontian, where an unusual mineral was found in 1790.
But strontium has a dark side too. Radioactive strontium-90 is one of the most dangerous products of nuclear blasts and accidents. It's chemically similar to calcium and accumulates in bones, irradiating bone marrow for decades. After Chernobyl, strontium-90 became one of the main contaminants.
You encounter strontium daily without suspecting it. Strontium ferrite (SrFe₁₂O₁₉) is the most common material for cheap permanent magnets. Fridge magnets, speakers, small motors — all strontium ferrites.
In medicine, strontium is used to treat osteoporosis (strontium ranelate) and pain from bone cancer metastases (isotope ⁸⁹Sr). And isotopic analysis of strontium in tooth enamel lets archaeologists determine where a person was born.
Non-radioactive strontium is low-toxicity — no more dangerous than calcium. But metallic strontium is reactive: burns in air and reacts with water. Stored under kerosene or argon. The real threat is strontium-90: it accumulates in bones, irradiates bone marrow, and causes leukemia and cancer. Half-life — 28.8 years.
Strontium was discovered near the Scottish village of Strontian in 1790. The mineral was so unusual that the element was named after the village.
Strontium's red flame is visible from 30 km away. That's why it's used in maritime rescue signal flares.
Strontium-90 accumulates in bones instead of calcium and irradiates bone marrow for 28.8 years — one of the most dangerous radioactive isotopes.
Strontium ferrite is the most common permanent magnet material. It's 10 times cheaper than neodymium, though weaker.
Strontium isotopes in tooth enamel 'remember' the birthplace. Archaeologists trace ancient migrations using this 'chemical passport'.
| Isotope | Mass (u) | Abundance | Half-life | Decay |
|---|---|---|---|---|
84Sr | 83.913425 | 0.56% | stable | — |
86Sr | 85.909260 | 9.86% | stable | — |
87Sr | 86.908877 | 7.00% | stable | — |
88Sr | 87.905612 | 82.58% | stable | — |
90Sr☢ | 89.907738 | synthetic | 28.8 years | β− |
Analysis of strontianite