Alkaline-earth metal strontium are the smallest element in abundance. The main ore minerals are celestite and strontium carbonate. It can be electrolysis of molten strontium chloride and obtained.
It is used to make alloys, optical tube, as well as analytical chemistry, fireworks and so on. Mass number 90 is a radioactive isotope of strontium, can be used for β-ray sources, half-life of 25 years.