Uses

Beryllium's principal industrial role is in alloys — copper-beryllium alloy is prized for high-strength springs, and metallic beryllium itself, being nearly transparent to X-rays, is used to make the windows of X-ray tubes.

Magnesium forms useful alloys with aluminium, zinc, manganese and tin; the light magnesium-aluminium alloys are widely used in aircraft construction. Magnesium in powder or ribbon form burns with an intensely bright light, exploited in flash powders, flashbulbs, incendiary devices and signal flares. Medically, a suspension of magnesium hydroxide in water — milk of magnesia — is a common antacid, and magnesium carbonate is a standard toothpaste ingredient. …