Granite Countertop Color After Sealing

QUESTION:

I just had new venetian gold granite countertop installed in my kitchen today. Unfortunately the largest piece had to be re-cut due to the granite company's measuring errors.


They cut a new piece and brought it out immediately but it is visibly darker than the rest of the granite.

They said it's due to the fact that the slab was just cut and was still wet from cutting and from the granite sealer and that it should lighten up to match the rest.

It has now been 8 hours and there has been no change in color. Is there a chance that it will still lighten up or should I prepare myself for a battle with the granite company?

ANSWER:

While it is true that the granite countertop color will darken when/if water absorbs and/or right after applying a granite sealer... there's some potential holes in their story and a more likely reason.

First, if the new re-cut granite countertop piece was still wet, then they shouldn't have applied a granite sealer.

Sealing granite countertops should be done with a completely clean and very dry surface, so you don't seal in any water or moisture.

Now, on a countertop this is not too much an issue since the underside is exposed to air and moisture can still evaporate. So long-term, it probably wouldn't be an issue like it would on new floors where the water would definitely be trapped.

But, it's just not the right way to do it.

Second, a typical impregnating granite sealer like these recommended marble & granite sealers should not darken or change the color at all.

A "color-enhancing" sealer will darken the color, but they wouldn't be applying a color-enhancing granite sealer in this case.

Third: Unless the granite countertop slab was completely saturated with water from cutting (possible with some stones) then whatever water did absorb during the cutting should be evaporated after 8 hours.

But if it was saturated, then you won't notice a change in color until the granite countertop is completely dry.

Since water is moving from the middle to the surface to evaporate the surface will be wet until the very last of the water evaporates.

At this point, I'd still give them the benefit of the doubt. Wait another couple days. If indeed the color change is due to water absorption, then you should start to see dry spots emerge along with the granite color getting lighter and eventually the whole thing should be dry and uniform in color.

Another possibility unfortunately is that there was not a slab from either the same "bundle" and/or even from the same "lot" as the original and they just picked up a slab that was as close as possible or... since this is a fairly common granite color, they used a piece they already had in the shop left-over from another job.

Granite slabs come to the warehouse cut like a loaf of bread. A "lot" is made up of a bunch of "bundles". If you need two or more slabs for a job, you want to get them all from the same bundle preferrably or at least from the same "lot" or you risk the slabs simply not matching.

Although the color will be very consistent in a bundle and even in a lot, the pattern can change or elements of a the pattern can change, so there is definitely an art to matching color and pattern when choosing and cutting granite countertop slabs.

So, it would be fine for them to simply replace only the area necessary, IF they can get a good match.

However, any reputable, honest granite countertop fabricator will recognize that mis-matched slabs don't cut it and if a match can't be made, then they simply need to tear it all out, eat the cost and start over with matching slabs.

Again, maybe their explanations are absolutely correct, but if after 2 days you see no change, then yes... prepare for battle.