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Portlandite

earth science Maturity 7-9 Next article →

Some rocks have a special part.

It is found in many places.

It can form near hot steam.

It can even come from coal.

This part helps make cement.

It is a neat find!

Can you find a rock?

39 words

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A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.