very strange indeed...what color was the grout? how was the stone set?  It looks like mold or mildew but cant say for sure..Try taking a couple of drops of bleach and see it removes the black..If it does it is a biological. Where is this located?  what part of the country<br>
<br><div class="gmail_quote">On Sat, Apr 3, 2010 at 8:21 AM,  <span dir="ltr">&lt;<a target="_top" href="mailto:info@restoreyourtiles.com">info@restoreyourtiles.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Did you seal that stone before or after grouting?<br>
Sent via BlackBerry from T-Mobile<br>
<div><div></div><div class="h5"><br>
-----Original Message-----<br>
From: &quot;Mike Marsoun&quot; &lt;<a target="_top" href="mailto:nulifesc@bigpond.com">nulifesc@bigpond.com</a>&gt;<br>
Date: Sat, 3 Apr 2010 21:56:34<br>
To: Restoration and Maintenance&lt;<a target="_top" href="mailto:sccpartners@stoneandtilepros.com">sccpartners@stoneandtilepros.com</a>&gt;<br>
Subject: [sccpartners] black stains on Sandstone<br>
<br>
This is strange. For a friend who is a supplier. There is 3 photo&#39;s that say<br>
grouted section.  This black started not long after grouting, mainly around<br>
were they cleaned off the grout.  It seemed like the grout contaminated the<br>
stone.   So 80% of the wall they did not grout and<br>
was looking good until a couple of weeks ago, and now that is starting to go<br>
too.<br>
Mike Marsoun<br>
Nu Life Stone Care<br>
<br>
<br>
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