I just sold an old Warner stove which was way too big for me in a house I recently bought. Going to replace it with a Jotul. The granite underneath the stove is discolored and I assume it was from the heat as it is in the outline of the old stove. The Jotul is not all long and the discoloring will show. Anyone have any suggestions as to what might brighten the discoloring up? Thanks for any suggestions.
Hearth Discoloring
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Are you sure that's granite? Looks more like something porous to me - slate? If it is something porous, I would guess either salts from moisture coming up through the stone (what's under the hearth?), or the result of applications of sealer drying.
It probably is some type of fieldstone or slate. Why would it only be discolored under the outline of the old stove?
With the pervasive use of stone these days, even HomeDepot probably has a cleaner. You may be surprised by what you find. The area under the stove may be the cleaner part. Especially if a sealer was used. In the past I have cleaned porous rock with a very stiff bristle brush(not metal) and TSP (tri-sodium-phosphate) a brick-layer may suggest mortar cleaner (usually some form of acid based cleaner - muriatic acid) It will at worst even the color out some. If you are not satisfied, there are some tinted sealers, but all will darken the stove.
CarbonNeutral said:
Calls for a tale from the past. Once did a table restoration for a customer. He was a science teacher and his wife for Christmas bought his old lecture table at surplus from the College. I restored the base and fixed all the things to work like new, even got some lab glass and made a funky bars decanter set. She didn't like the top, called it a crummy black rock, too dull for her house. So I took a quick lesson in polishing. Now I have two of the best wet sanders on the market, and I worked my butt off for three days and almost a sleeve of SC paper and powders so fine it was like talc. She loved it when I was done. I delivered it just before Christmas and got a rave review.
Got the table back just after New Years, the top looked too good to him, could I dull it down and add some stains????????
Well, I can think of a couple possibilities:
1) Ash. Ash can get in to all sorts of stone work and leave a cloudy appearance even though it was wiped/swept/vacuumed up. If the stone is porous, the problem is worse. You might try a product such as 'Lime Away', 'CLR' or something similar to help remove the ash. Sealing the stone should help - but only once you get it to the look you want, otherwise you're just sealing the discoloration in.
2) Efflorescence. Sometimes heat/cool or wet/dry cycles can pull salts out of stonework - especially concrete and brick. The water evaporates from the surface and leaves salt behind. The best way to remove this would be to wash/scrub the surface with water to dissolve the salt, then rinse with clean water until the salt is gone.
3) Sealer Damage. If the stone was formerly sealed with a non-penetrating sealer (ie one which forms a coating on top) - that sealer could be damaged by heat from the stove, caustic ash, etc. In this instance, it's probably better to use a stripper or mechanical means to remove the sealer. A penetrating sealer is less prone to heat damage and would leave the stone with more of a natural look.
1) Ash. Ash can get in to all sorts of stone work and leave a cloudy appearance even though it was wiped/swept/vacuumed up. If the stone is porous, the problem is worse. You might try a product such as 'Lime Away', 'CLR' or something similar to help remove the ash. Sealing the stone should help - but only once you get it to the look you want, otherwise you're just sealing the discoloration in.
2) Efflorescence. Sometimes heat/cool or wet/dry cycles can pull salts out of stonework - especially concrete and brick. The water evaporates from the surface and leaves salt behind. The best way to remove this would be to wash/scrub the surface with water to dissolve the salt, then rinse with clean water until the salt is gone.
3) Sealer Damage. If the stone was formerly sealed with a non-penetrating sealer (ie one which forms a coating on top) - that sealer could be damaged by heat from the stove, caustic ash, etc. In this instance, it's probably better to use a stripper or mechanical means to remove the sealer. A penetrating sealer is less prone to heat damage and would leave the stone with more of a natural look.
Slate: (broken link removed to http://www.stonecare.com/Types-of-Stone/Slate/Kitchen-and-Foyer-Floors/)
Thaks for the info....will start with water...move to the acids...and then try sealing to darken if need be.
I know oxalic acid (do a google search) will take the stains out of wood or even cement. But i am not sure you can use it on your type
stones. You mix it with water and make a slurry. Then brush it on..wait..and then wash it off. You may want to research it to see if
it will work with your stones. I have refinished antique oak furniture with deep black water rings in the wood and oxalic acid has taken them
right out after a few applications. Give it a look and let me know if it works for you.
stones. You mix it with water and make a slurry. Then brush it on..wait..and then wash it off. You may want to research it to see if
it will work with your stones. I have refinished antique oak furniture with deep black water rings in the wood and oxalic acid has taken them
right out after a few applications. Give it a look and let me know if it works for you.
The tip for oxalic acid (well any chemical really) : wear gloves and don't get any on your skin. Oxalic acid is the key ingredient for the calcium / lime / rust dissolvers. When absorbed through the skin it will just as happily dissolve calcium from your body and deposit in your kidneys as calcium oxilate - aka 'kidney stones' - nobody enjoys passing one of those!
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