Stone and Tile PROS | Natural Stone, Tile, Concrete
FOR PROS ONLY : BACKSTAGE
Your Stone and Tile Information & Resource Super Site
Home » Categories » Care and Maintenance

Black Granite Fading - Doctored Stone

Black Granite Fading

By Frederick M. Hueston

I have received numerous calls lately concerning the fading of black granite countertops.

The most common complaints seem to be on Absolute Black, Black Galaxy, Zimbabwe Black and a few others. I have heard many fabricators try to blame the fading on the misuse of cleaning chemicals, acids etc.While one should not use inappropriate chemicals on granite surfaces, this is not the reason for the increase in black granite fading.

Why does black granite fade?

The answer is, real black granite should not fade. Black granite imported from Asia and India is sometimes gray granite doctored with dyes and oils to darken the surface. Dyes can include home made blends such as charcoal and linseed oil. Pre-packaged color enhancers are also used to darken granite. The fading is nothing more than the dyes and oils being removed. Of course the wrong chemical will take the dye out faster but I have seen many of these dyes removed using simply water and a mild cleaner.

Testing for Dyed Granite

Before purchasing a granite slab perform the following test to find out if it has been doctored.

Take a clean white rag and apply some acetone to the surface of the granite. If any residue or black color is observed on the top, do not accept it, it has been dyed. If you get no dye from the acetone, then take some MEK (Methyl Ethyl Ketone) and apply to a different part of the slab. If you get any color transfer the stone is dyed. These chemicals can be purchased at most home improvement or paint supply stores.

Can Dyed Granite Be Repaired?

The reason granite is dyed is that its natural color is gray and it doesn't have that deep black color that some black granites have. For this reason many factories use deceptive methods to doctor these slabs pawning them off as deep black granites.

Unfortunately, there is no fix. Other than to dye the granite again.

In addition to dying, many types of granite are also injected with resins, which can also darken granite. For further information on the resining process see my article titled Resin Slabs, The Good, the Bad and the Ugly.

Attachments Attachments
There are no attachments for this article.
Comments Comments
There are no comments for this article. Be the first to post a comment.
Related Q&A's RSS Feed
How to remove calcium build-up on headstone
Viewed 7670 times since Tue, Oct 13, 2009
How can one remove hard water deposits (probably from calcium) from granite?
Viewed 2386 times since Thu, Dec 25, 2008
etch spots on polished travertine
Viewed 2186 times since Thu, Jan 15, 2009
Are you aware of whether stripper would damage/weaken the grout between the tiles?
Viewed 1893 times since Fri, Aug 22, 2008
limestone with mold / mildew stains in grout joints.
Viewed 6731 times since Sun, Jul 11, 2010
Help! My cleaning lady spilled diluted bleach or something that etched my crema marfil marble.
Viewed 2200 times since Thu, Aug 21, 2008
Can cement tiles or ceramic tiles be installed on top of Corian or Avonite?
Viewed 2185 times since Wed, Jun 2, 2010
Should I polish and seal my new marble flooring?
Viewed 3030 times since Tue, Nov 17, 2009
Crack In Newly Installed Quartzite Island Top
Viewed 15571 times since Tue, Mar 26, 2013