[LerchBros]

Has anyone ever had a customer complain about inconsistency in mortar color? We installed a quartzite stone walk in mortar and the customer had us replace a couple of stones he didn't like. Once the stone were replaced and pointed, the color was different. I understand that curing time has a lot to do with the color and thats fine, but there is still a drastic difference. Now the other confusing part is that we used ready mix bag mortar on the entire job! How can the mortar be that far off????? The bags all came from the same pallet. The only thing i can think of is the temperature differences. Some of the work was done around freezing and some done in the 40's.

Now that the little things are out of the way. How do i fix this ???? I do not want to re-point the entire job. Will muriatic acid etch the mortar enough? Is the lighter color mortar just a surface color?? Should i use something more abrasive? Is there a dye?

All opinions welcome....

Thanks GTX

[Stonehenge]

It could have been the temps, or also the moisture content of the two different mortars when they were applied, as well as the relative humidity on the different days.

What will fix it? Time. I'm sure the client won't want to hear that, but if he gives it 6-12 months, the two colors will match. That's what my mason told me when I freaked about the color matching of mortar done on different days on some work he was doing for me, and he was right.

[LerchBros]

Those were my thoughts. The mixture of the mortar is consistent, enough so that you should not be able to notice a difference in color. Its straight Type-S mortar mix. The homeowner feels that the difference in the amount of water used in the batches made the mortar change color. I disagree. Yes some of the mortar slumped more than the rest. However, the water evaporates and if there was too much water the joint would have contracted and pulled away from the stone while curing. I am going to acid wash it and see what happens. If he complains I'll just keep dragging my feet for about 6 mos.

Thanks,

[Fine Edge]

I think time is the only way. It will match if given enough time.
How far apart were the 2 jointings done? Has the last jointing had enough time to thoroughly dry?

[LerchBros]

The pointing was done and the repair work was done a week later. It's been about two weeks since we have been to the site (it's been snowing off and on) I am going to go and see what it looks like tomorrow.

Should I put any faith into the muriatic acid ???

Thanks

[Fine Edge]

I didn't think the acid would change any color but would more or less remove most of the dried mortar from the stones and give them a good cleaning.
I'm just not sure what the acid would do to help you out in this situation.
Again, I say you wait it out.

[LerchBros]

Unfortunatey i have to take some action because of the homeowner. I'll acid wash and see what happens, maybe the mortar will all be the same color once that top layer is removed? Hopefully it will give me some more time. I guess i'll just have to wait and see.

Thanks again guys.