Beryllium 铍
（重定向自Berylium）
![](/Images/godic/202412/24/Be-140g3450.jpg")
![Plot showing variations in solar activity, including variation in sunspot number (red) and 10Be concentration (blue). Note that the beryllium scale is inverted, so increases on this scale indicate lower 10Be levels](/Images/godic/202412/24/Solar_Activity_Proxies3450.png")
![Beryllium ore](/Images/godic/202412/24/Beryllium_OreUSGOV3450.jpg")
![Emerald is a naturally occurring compound of beryllium.](/Images/godic/202412/24/Beryl-1300233450.jpg")
Beryllium is a chemical element with symbol Be and atomic number 4. It is created through stellar nucleosynthesis and is a relatively rare element in the universe. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl (aquamarine, emerald) and chrysoberyl. As a free element it is a steel-gray, strong, lightweight and brittle alkaline earth metal.