Most granite is porous to a certain degree and thus susceptible to staining.
Least porous granite.
Porous materials such as granite marble and concrete need to be sealed regularly about every six months says courter.
Marble countertops are very porous and require re sealing once every few months.
Even worse germs bacteria and mold can invade unsealed granite counter tops with stains running not far behind.
Like all natural stone granite is susceptible to liquid sinking into its surface.
Strictly speaking some tests measure the accessible void the total amount of void space accessible from the surface cf.
There are many ways to test porosity in a.
Porous materials have minute surface holes that liquids may penetrate leaving stains and eventually eroding or cracking the surface.
By comparison a more stain prone granite like kashmir white has an absorption rate of 3 5 and would definitely need sealer.
Much like granite marble is one of the most common countertop materials chosen by homeowners.
Staining can be easily controlled by application of a sealer on these surfaces.
Btw i looked up the absorption rate of my granite and it is 1 3.
Alas its porous surface is granite s kryptonite.
How porous is granite compared to marble.
Empty spaces in a material and is a fraction of the volume of voids over the total volume between 0 and 1 or as a percentage between 0 and 100.
Also granite is immune from the damages of most common household acids.
But while granite is one of the least porous natural stones that is not the case with marble.
Porosity or void fraction is a measure of the void i e.