They're

  only

Adverbi

  made of

  rock crystal

,  and

Conjunció coordinadora

  there are

  millions

substantiu

  of

Adposició

  rock crystals

  in

Adposició

  the

Determinador

  earth

substantiu

.

They're only made of rock crystal, and there are millions of rock crystals in the earth.

They're only made of rock crystal, and there are millions of rock crystals in the earth.