White carrara marble turned yellow after installation

[ob1kanobee]

John, thing is with tops, is that there is a whole lot of water being used when they are made and I have seen them sit out in the stone yard after and before.

Bottom line is Designers and other folks are still going to want this stone installed in showers and on tops. I don't blame them, it's beautiful. White just happens to be my favorite color.

I would just use a disclaimer and every conceivable setting method available to try and mitigate it. Cover your butt when you install this white marble 'in writing' and recommend against it, just have them sign off.

Found another site about it to but I had to be a member to gain information on the study involved......maybe it was just the same study I don't know......

[MarkTarkus]

Thank you Ben and John and all others who have input on this. I appreciate the help. As Ben said, white marble is popular right now. I do have a few more jobs scheduled to install it. I think the disclaimer is a good idea. I'm not too excited about tearing the whole thing out, I think for now I will replace the yellowed tiles and take my chances on this one. I have talked with my supplier and I see no fault of theirs. How would they know the mineral content of any particular box of stone? At the same time I am confident with my installation and don't believe that I did anything to have caused it. I do wish I would have known about some of the other precautions to take but too late now. In your opinions, do I take the bullet on this one and eat the cost or do I try to get the supplier to help with it?

[doitright]

Hi Mark

If you have good relations with your supplier, I would certainly give it a go. It never hurts to talk about it, and what your future plan of action is for prevention. All they can do is say no. Unfortunately, many business's are suffering right now. Letting a few boxes of stone go out the door might not be bad PR for your supplier though. That word can be spread by your client, as well as yourself on how everyone pitched in to handle an unanticipated situation.

[ob1kanobee]

I think it would be a nice gesture on their part to at least replace the material you need to redo the tiles you plan on changing out. I don't see why that would be a problem even though I don't feel they are under any obligation to do so.

I have been on both sides in this business and there really is no fault in this whole thing. Live and learn............it's natural stone

I would take the precautions on the replacement tiles. It might be a good indicator or field test.

[Headaman]

Sorry, but I'm about to install Carrara that I bought almost 4 yrs ago. It's been patiently waiting for me in the garage. I looked up Laticrete 9235 on the Laticrete website. It's a rubberized 'paint' and a waterproofing membrane. I'm assuming when the advise to use 9235 on the backs of the marble it's just the liquid portion. The 'helpful tips' state that 9235 turns from Dark blue when wet to BLACK when dry. Uhhh, forgive my ignorance, but that's not good for White Marble, right?

What else will work?

Thanks

[ob1kanobee]

Laticrete Hydro Ban is a real light color I believe. If you look over to the right at the advertisers, you will see it.

Where are you using this marble, in the shower?

Have any details about your project?

This might not be necessary unless it is going in a wet area.......

[Headaman]

Yep, in the shower. 12"x12"'s on the wall and mosaics on the shower floor. I have a post I put up with Kerdi and backerboard questions earlier today.

Okay, so I looked up Hydroban. It's light green and drying to a medium soft "moss" green if you will. Hydro Barrier is bright blue.

It's also rubberized. Will that stick to the unmodified thin set 'required' by Schluter for Kerdi to tile?

[ob1kanobee]

I wouldn't recommend it. I'm no pro with Kerdi but I also think some of the guys on here use a slightly modified thin-set with Kerdi like Versabond. We might need one of the other guys or perhaps CX to chime in on this.

HOWEVER:

You could scratch coat/burn the backs of the Laticrete with a modified recommended thin-set for Hydro Ban and then use a non-modified thin-set to actually stick it to the Kerdi. I can't see a problem with that. That's how I would do it.

[doitright]

Hi Heather, Welcome!

You're in a tough situation. Of all the Carrara showers & floors I've done, I've yet to have an issue such as the one mentioned in this thread.

Another option is you could use a quick set thinset (without the Hydro Ban) over the Kerdi. However, nothing is guaranteed.

The problem with this material (as Ben commented), is it is a natural stone. It may or may not have the pyrite content. If you were to have it TESTed, it costs big $$$ (approx. 1500 of them). That would only give results for the piece TESTed.

[PeteD]

Natural variability is of course part of the deal with stone, but the manufacturers should have some idea of the quality of the stone and be able to grade the stone to some degree. Geologist should be able to determine what areas of marble deposits may be higher in iron or pyrite and plan their product accordingly. In addition, the quarries could certainly do some testing to identify these problem areas, if they cannot be identified by geologists using conventional means. I am not sure how common this problem is, but it does not seem very widespread.

Does anyone know how long it takes to manifest itself? It seems like the manufacturers could season their marble (expose to air/water as required) for however long it takes in the large slab form to judge the quality of a particular slab or area of their quarry...maybe this really happens on a micro-scale and it is not avoidable at all, but I am not sure.

It seems like it may be QC problem where some bad product slips by every once in a while....keeping my fingers cross on my order of Carrara.

I will definitely talk to my supplier and see if he has seen it.

Pete

[Dfly]

It worked for me once...

Iron Out from Lowe's

http://www.lowes.com/lowes/lkn?actio...65N&lpage=none

[PeteD]

The more I research this issue, the more it seems like this yellowing is at least somewhat likely to occur with some frequency in white marble from Italy, when exposed to water on a consistent basis.

This indicates that good installation and sealing techniques are needed, especially for showers.

Maybe the tiles were exposed to water before the OP received them and the oxidation did not show until after the install (just bad luck fluke of timing)?

Since Mark says he mixed boxes and it seems like a well-done install, maybe these were the bottom tiles in several boxes stored on a damp floor at some point before being installed?

The pattern is definitely odd and point to a non-random cause...hopefully the homeowners are being honest about not touching the tile, since there are quite a number of references to different cleaners and treatments potentially causing this yellowing...

Pete

Interesting Link:
http://www.stonebusiness.net/index.p...neral&Itemid=2

[GeorgeT]

This is an issue we are asked about on an infrequent but consistent basis.
The problem appears common.
It seems there is an iron mineral content to the Apuan Alps Italian white marbles. Statuario, venato, bianco goia, etc., can all exhibit this problem....
The stone Calaccata d'Oro with that gold colored vein ... thats a yellow-orange vein caused by ferric minerals.

Sometimes, like problem in this thread, the oxidation covers the tile. Sometimes it is little round orange spots that grow.

Sealer are designed to be vapor permeable, it makes this issue impossible to seal against it... Steam showers are the most common place I hear about this issue...Steam, a vapor, goes through sealers adding dampness to the stone and acts on the minerals.

Not to say there may not be another cause, but the use of improper cleaners or products usually leaves telltales; wiping marks, drips, runs, or spray patterns.

The pictures look like the even, gradual color of mineral oxidation...

[Stephen G]

My experience in this regard was with white carrara tiles, I guess ex China. With hindsight some of the tiles had come apart from the nylon mesh backing and were replaced by hand on the mesh. The tiles that were placed back on the mesh had a kraft / yellow paper backing. After placement and after a couple of weeks it was these tiles that turned yellow. I then had the task of sawing out individual tiles and replacing paper backed tiles one by one with nylon backed ones.

[doitright]

Hi Steven, Welcome!

Thanks for your input. Goes to show that there are many variables when working with natural stone. Throw restoration into the formula and you have a consistent challenge.