Page "Relative density" Paragraph 1

If a substance's relative density is less than one then it is less dense than the reference ; if greater than 1 then it is denser than the reference.

If the relative density is exactly 1 then the densities are equal ; that is, equal volumes of the two substances have the same mass.

If the reference material is water then a substance with a relative density ( or specific gravity ) less than 1 will float in water.

For example, an ice cube, with a relative density of about 0. 91, will float.

A substance with a relative density greater than 1 will sink.