Using AGER To Darken Granite Countertop Edges
We recently had Santa Cecilia granite countertops installed in our kitchen.
The stone has a beautiful golden hue...
We were disappointed that the edges appear much lighter/whiter
than the rest of the stone after installation.
We had read that some stones are treated with a protective agent prior to shipment and when they are cut during fabrication the true color is revealed.
The fabricator should have treated the edges with an AGER product to darken them prior to the polish and seal process.
Our installer did come out to the house to apply this product after the project was completed, but it was not effective. Is there a way to darken the edges after the edges have been sealed?
ANSWER: Yes, Tenax Ager is especially formulated to darken the cut edges of granite countertops so that the edges match the color of the top surface particularly if it has been resined.
It is meant to be applied during the process of polishing the edges but can be applied at any time to any type of finish (honed, polished, etc.).
The edge cuts are made at the fabrication shop. Usually, the edges are also polished at the shop before bringing the cut slab to your house for installation.
During this edge polishing process the Ager is applied by applying a coat, then polishing, then another coat (if needed) and polishing. This way you can get the closest color match.
Why are granite countertop edges lighter in color than the top surface?
Some granite countertops
(and other natural stones) are "resined" to fill imperfections and to better bind the stone prior to polishing and transport, etc.
This resin will darken the granite slab color some. The slab is then cut for installation. The edges of the cut slab must be polished to match the top surface finish.
However, since the top has a resin on it and the edges do not, the edge color won't match the top color even after polishing the countertop edges
. The polishing process brings out the color
making it deeper and darker by changing the way light reflects off the surface.
So, a polished surface always has a deeper/darker color than the "natural" color of the granite,
which can always be seen by simply looking at the underside of a granite countertop or on the non-finished side of any stone slab. But if a resin was applied
(or other color-enhancing product) to the surface, then yes... it would need to be applied to the cut edges as well or they will be a different color than the granite countertop.
Of course, the same resin that was applied to the slab at the factory is not available during installation, so some other type of color-enhancer must be used to try and match the edges. Color-enhancing sealers
are designed to be applied to a honed surface to darken the color and give it that "wet look".
Typical color-enhancing sealers are not meant to be applied to a polished surface, although, sometimes experimenting can yield a match of the edges with the top surface. To solve this edge color mismatch Tenax Ager
is applied. This product is more versatile. It works like other color-enhancers and can be applied to honed stone surfaces. But it also has proven to be effective on polished surfaces which works great for a granite that has been resined.
It is applied after
polishing the edges, but before
any other sealer is applied.
A color-enhancing sealer must applied before
a standard impregnating sealer is applied, otherwise the enhancer / Ager won't absorb well or at all.
Since the sealer has already been applied, you could try stripping the sealer off the edges using methylene chloride.
If not possible or not as effective as needed, then really your only remaining option is to grind the edges a bit to expose some raw granite and start over.
First, polish the edges, then apply the Ager using as many coats as needed to get the best color-match to the countertop surface. Applying a standard impregnating granite sealer
over a color-enhancing sealer is the common method.
Enhancers are not typically great sealers and are used primarily to darken color. But recall the majority of enhancers are used on honed stone which is more porous than polished stone requiring better sealing.
However, on edges the risk of staining is near zero, so applying the Ager (and no other sealer over it) will be more than sufficient.