## Solids and Metals - Specific Gravities - Engineering ToolBox

The Specific Gravity - SG - is a dimensionless unit defined as the ratio of density of the material to the density of water at a specified temperature. It is common to use the density of water at 4 o C (39 o F) as reference - at this point the density of water is at the highest.. Specific gravities - SG - for common solids and metals can be found in the table below: