A Visual Encyclopedia of the Periodic Table

74

Transition Metals

Forms

Yttrium

Y

39

The samples of rock brought back from the

Moon by astronauts in NASA’s Apollo

missions contained higher levels of yttrium

than rocks on Earth. This element is never

found in pure form in nature, but small traces

of it are present in many minerals, including

xenotime and monazite. Yttrium was

discovered in a compound in 1794 by the

Finnish chemist Johan Gadolin, but it wasn’t

isolated until 1828. Other yttrium compounds

have since been found in vegetables, including

cabbage, and in seeds of woody plants. In

Yttrium

is^400

times more

common in

Earth’s crust

than silver.

Xe

no

ti

m

e

This reddish-brown mineral

contains about 2% yttrium.

This

vegetable

contains

yttrium.

This mineral

contains trace

amounts of uranium,

which is radioactive.

This rock sample was brought to

Earth by NASA’s Apollo 16 mission.

This silver y

element does not

corrode easily.

Monazite

Mo

on^ ro

ck

39 39 50

State: Solid

Discovery: 1794

C

a

bb

ag

e

Laborator y sample of pure yttrium

074-075_Yttrium.indd 74 12/12/16 5:38 pm