Construction & Contractors/Stone Hearth


QUESTION: Hello, We installed a natural stone hearth - bluestone - which we sealed with a petroleum based impregnator sealer before grout was applied. After the grout was applied, we now have a haziness that extends about 3 inches away from the grout line and it also shows a whitish spotting.  I have tried stripping the sealer and resealing it but it still shows the haziness and whitish spots.  Are there products available to help with this so I can start all over?
Thanks so much!

ANSWER: Jolene,
It sounds like there is residual grout haze absorbed into the stone. I would suggest using the HMK R55 Intensive Cleaner: to help remove the grout residue. You may need to repeat process. I would mix 1-part R55 to 4-parts warm water. Scrub area and allow solution to soak in for 20 minutes, scrubbing every 5 minutes for 1-minute duration. Rinse very well and allow to dry. Observe surface, and repeat if necessary.

If the grout was absorbed deep into pores, you may need to use a more aggressive option, an acid base cleaner:

I always suggest the mild option first,(R55) and then progress to more aggressive option if neeeded.

Best wishes,

---------- FOLLOW-UP ----------

Hearth Stone Picture
Hearth Stone Picture  

Hearth Stone Picture 2
Hearth Stone Picture 2  
QUESTION: Hello Torin, Thanks so much for your answer to my question about the hearth stones.  I am including an image of the haziness.  I plan on using the products that you recommended in your answer.  My question is should I seal the area that I clean after I clean it?  If so, what type of sealer should I use?
Thanks so much!

Your images show more residue than I thought. You may indeed need to use the acid cleaner, but we always suggest using the mild solution (R55) first, before graduating to the acid cleaners.

Yes, after getting residue cleaned up, I highly suggest using the professional grade S34 Silicone Impregnator:

Try to remove residue first with the R55. It is a truly amazing product. I recently cleaned a shower with R55 that I thought was beyond hope. It had been neglected for years. The R55 cleaned and restored the delicate marble from Spain.

Best regards,

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Torin Dixon


Questions concerning Natural Stone Fabrication and Installation including: Marble, Granite, Limestone, Slate, Soapstone, Bluestone, and Travertine in Slabs and Tiles. Expert in natural stone cleaning, sealing, protection and restoration. Distributor of HMK Stone Care Products; Sealers, Cleaning Products, Stone Maintenance. Expert in stone and tile flooring, sealing and maintenance issues. Stain removal from stone. Importer and Distributor of slab stone for residential and commercial applications. Stone carving Stone restoration


I have worked in the Dimensional Stone Industry since 1977.
California Contractors License 1989
Former owner of Prestige Marble & Tile (So. Calif.)
Current owner of Elegance in Stone (Missoula, MT)
Current Owner of Montana Stone Gallery,LLC Missoula, MT
Owner of Distributor of natural stone maintenance products

Missoula Building Industry Association
Montana Building Industry Association
Flathead Building Association
National Association of Home Builders
Member of the Marble Institute of America
Former member of the National Tile Contractors Association

Slippery Rock Gazette-Stone Industry Publication

Journeyman Marble Mason, Bricklayers and Allied Craftsman Union #2
California Contractors License 1989-1997
Montana Contractors Registration #70932IC
Importer of natural stone slabs. Owner-Director of Montana Stone Gallery a regional Importing and Distribution company located in Missoula, MT

Past/Present Clients
Thousands of commercial and residential installations of stone slabs and tile in bathrooms, kitchens, showers, flooring, fireplaces over a 34 year professional career.

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