Prosoco makes a Heavy duty concrete cleaner that wiil remove real bad grout smear. If it isn't that bad you can use one of their other products called VanaTrol.
From: "Majestic Stoneworks" <firstname.lastname@example.org>
Subj: [sccpartners] removal of mortar from slate
Date: Wed Feb 25, 2009 4:02 pm
Size: 1006 bytes
To: "Restoration and Maintenance" <email@example.com>
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