hi partners,<br><br>what methods do you employ to clean very dirty grout lines (black now, was off white when installed).  i need to do 3 hones a polish and then seal to renew the white marble ( about 390 sq ft) the grout lines are about 1/8&quot; and the customer does not want to regrout.  <br>
<br>thanks.......barry<br clear="all"><br>-- <br>Thank You,<br>Barry V Raduta<br>Diamond Stone &amp; Tile Care<br>215-816-7689<br>