I have seen this before, I think this is "bleed in" from the rubber backing 
Of a bath mat.  Next to the toilet ,just a small amount of dampness from urine will cause this. I think if you poultice with acetone and DE this should come right up 
My two cents
Best Regards
Scott Wilson
Wilson Stoneworks Inc

Sent from my iPad

On Jun 12, 2018, at 3:52 AM, Fred Hueston <fhueston@gmail.com> wrote:

Could be they used a mastic to set the tiles and its bleeding through. Also check for iron

On Tue, Jun 12, 2018 at 1:49 AM, Stephen Webb <stephen@newlifemarblerestoration.com> wrote:

Just in that area? Ask them if they apply spray on sunscreen there. Ive seen it do that


On 6/11/2018 6:15 PM, Tony Deluna wrote:
Hey Pro’s, A customer sent me this picture. Does anybody know what might cause these orange patch is in the middle of the tiles?

Thank you in advance for your response


 
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Tony DeLuna
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