Countertop Education: Stone Absorbency Test


A few weeks ago we wrote about when and how to seal your natural stone.  In that post we mentioned something called the absorption coefficient.  In case you missed that post or need a refresh, basically the absorption coefficient is how porous your natural stone surface is and how quickly it will absorb a liquid.

It’s important to know the absorption coefficient of your natural stone so you can choose an appropriate sealer.  Below we’ll tell you how to determine how absorbent your stone is.

First you’ll place a few drops of water on the surface of your stone.  You’ll need to time how long it takes for these water drops to disappear completely.

  • If the water disappears in under one minute consider your stone very porous.
  • If it takes up to 3-4 minutes, consider your stone porous.
  • If it takes more than 3-4 minutes, consider your stone slightly porous.

This test is also helpful in determining how much sealer you will need to adequately seal your stone.