A Visual Encyclopedia of the Periodic Table

48

Alkaline Earth Metals

Petal-like shapes

form in the desert

when sand mixes

with barite

or with gypsum.

This mineral is used

to make ceramic glazes.

This soft metal

has a light,

golden shine.

These glassy, blue

cr ystals contain

barium and titanium.

Forms

Barium

Ba

56

56 56 81

State: Solid

Discovery: 1808

Barium is named after the Greek word

bar ys, which means “heavy”, because

barium and its minerals are dense. The

pure form of this element was first discovered

in 1808 by the English chemist Humphry Davy,

who extracted it from an oxide of barium. This

does not exist in nature. Davy obtained it by

heating the mineral witherite. Today, the main

source of barium is barite, a mineral of sulfur

that forms in deserts and in rock deposits that

come into contact with hot water. A rarer mineral

called benitoite also contains barium. The

Farmers

used witherite as

rat poison

until the

18th century.

A grey layer of

tarnish forms when

the metal comes into

contact with air.

Witherite

D

e

se

rt

r

os

e

B

en

it

o

it

e

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