Abrasives and acid to remove it.
That slate looks flat so maybe dip’s
And or a brush
Do some testing 
I would try MB22 under a red dot vortex pad


Sent from my iPhone

On May 31, 2018, at 8:01 AM, Fred Hueston <fhueston@gmail.com> wrote:

First you need to find out why..Is it a grout film? efflorescence? etc
I have seen this happen with certain sealers as well

On Thu, May 31, 2018 at 7:58 AM, <csantospago@gmail.com> wrote:
Hi partners,

Will try to resolve this grout haze issue on this Brazilian honed slate on Saturday (pics below).
Apparently it’s just regular grout and they used dry treat to seal it.
Was installed several months ago so I will just try the least intrusive method possible and go from there.
Would appreciate any ideas
Thank you,
Chris Santospago
Restoration by design stone

Visit list archives, subscribe, unsubscribe or change your subscription
preferences:
http://stoneandtilepros.simplelists.com/sccpartners

Start a new conversation (thread):
sccpartners@stoneandtilepros.simplelists.com




Sent from my iPhone



--
Frederick M. Hueston
www.stoneforensics.com
office             321 514 6845      
Stone Inspection and Troubleshooting seminar June 11-14, Melbounre FL
For more details see the training section at www.stoneforensics.com
check out the Stone and Tile Radio Show at http://www.blogtalkradio.com/drfred  Airs every Wednesday at 6pm EST




Visit list archives, subscribe, unsubscribe or change your subscription preferences: http://stoneandtilepros.simplelists.com/sccpartners Start a new conversation (thread): sccpartners@stoneandtilepros.simplelists.com