Marble coping turned pink at install?

[melteye]

We're at the coping/tilling phase of our pool build and something appears to have been done incorrectly. Trying to understand what happened, but here's the gist.
- Last week, they installed most of the pool perimeter coping (tumbled marble).
- Yesterday, they did most of the raised wall in the same material and then it started raining so they left. The rain has continued through most of the day.
- Last night and today, most of the coping on the raised wall is turning pink. None of the coping on the perimeter which they did last week has gone pink.

Can you please advise on what the issue could be. I'm guessing (from my other experiences w marble inside the home) it can't be cured. It has to be replaced. This stuff is really pricey, the builder should be replacing it right? They are coming out tomorrow to take a look, but wanted some advise how to address. TIA!

 

[ajw22]

Post pics of the stones.

From searching it looks like it could be caused by iron in the stones.

A recommendation I found here Delicatus granite turning pink, need help!! is...

2 methods to draw out the pink, which doesn't always work but are the best that I have seen first hand. Miracle sealers sells a product called Poultice granite cleaner which is a paste that is spread onto the stone. You can also use baking soda to create a paste to spread onto the stone. These 2 pastes will draw the stain out of the stone. Depending upon the density of the stone, these methods don't always work 100% but they will help lighten the coloring.