Danger: Using Natural Cleaning Products Can Ruin Your Granite Worktop or Marble Floor

39 Comments

1. 

   Cathy

   April 30, 2010 at 6:07 pm

   How about for a ceramic tile floor? We have a new one in the kitchen & I have been using vinegar and water on it. Is that ok?
2. 

   Ian Taylor

   May 18, 2010 at 4:46 pm

   Very sorry, I thought I had answered this. Vinegar and water? – can’t really see a need, it should not harm the ceramic tiles (unless they are a metalic glaze and even then, not all metalic glazes are susceptible to acids). However it will do some thing to the grout, over time it will etch some of the cement, whether it is strong enough to do real damage is debateable but really the best advice is to use a neutral cleaner for reguloar or routine maintenance. And a stronger alkaline one for occasiona deep claning or cuting through grease.

   Ian
3. 

   Eva

   October 18, 2011 at 2:01 pm

   Hi.we are living in rented house and have black stone worktop in the kitchen,we always cleaned it with fairy liquid only,but when we tried to clean a limescale around the tab the product we used left slightly lighter stains! In feels like polish came of the stone.is there anything we can do to restore the colour and shine? Thank you
4. 

   Ian Taylor

   October 24, 2011 at 9:30 am

   Hi Eva,

   I am afraid this sounds like Acid Etching. First of all, you do not say what the black stone is but I am going to make an assumption that it is a black ‘granite’ and that it is polished. I say this as most black work-tops are polished and granite. The granite is in inverted commas because there are a variety of granite-like stones being sold as granite but they can be other stones, such as basalt, particularly from China. Why? Well it is much cheaper than ‘real’ black granite, it is just as nice to look at, can be worked exactly the same and can produce the high shine when polished, it is also a perfeclty good stone except in some cases for one thing – and that is that unlike real granite, it is sensitive to acid. (There are also some real grantites that have a small degre of acid sensitivity).

   The problem is that the black crystals are probably no damaged by acid, but the finer matrix that is present between them may contain a high degree of calcium and it is this that has reacted with the acid that was undoubtedly present in the limescale remover.

   If I have accurately described your situation, then I am afraid there is not a great deal you can do, you may be able to bring some colour back by using an enhancing sealer, but I have found this to be hit and miss. As far as the shine goes, some stone has been physically removed by the etching process, so to correct it properly the entire slab would need professionally refinishing, this can be done but it is going to involve a pro with the right tools and several grades of diamond pads – so is a time consuming and costly process.

   if you can get some colour back with an enhancer, you may be able to use a counter top wax type polish that gives some shine back but it wil be a bit like putting boot polish in scuffed shoes.

   If however, it is a black marble (not too popular for kitchen work tops as it is so easily etched) – then ironically, you may have a better chance with a localized application of a repolishing cream

   Sorry that may not be what you want to hear, if I can help any more or if you want any more infomration o professional restoration please do not hesitate to ask

   hope this helps

   Ian
5. 

   nicola de-haan

   January 7, 2012 at 2:04 pm

   hi, can i use vinager & water to clean my black granite floor tiles? they are very dull and nothing i use seems to be working.
   thanks
6. 

   Ian Taylor

   January 16, 2012 at 1:53 pm

   Hi Nicola,

   Your issue could just be a build up of dirt, and/ or detergenet resiidue. Often dull tiles come about due to lack of rinsing with detergents and over time it builds up a patina and dulls the surface, a good deep clean with a high alkaline cleaner would normally resolve this.

   I would strongly recommend that you DO NOT use vinegar in any form. There is strong possibility that your ‘black granite’ is actually basalt or some other similar stone. In fact, many geologists will tell you that there is no such thing as a true black granite, what you have is an igneous stone, formed in the same way and with very similar characteristics but not technically granite. There is no problem with this, the stone industry is allowed to describe such material as granite as it meets many of the criteria for that stone type.

   The main thing to be careful of is acidic etching, quite a lot of the so called black granites are susceptible to acid etching, in fact, this may be the reason that your stone has gone dull in the first place. If any of the black colour has turned greyish, that is another indication of etching. Unfortunately, there is liitle that can be dine to bring back the shine on this type of stone if this is what has happened, it may be that you need to seek the help of a professional stone restoration company (like Marblelife Ltd. for example) who may be able to re-grind and polish the stone back to its former glory – but, if this was possible then it it quite a costly process.

   Try the alkaline deep clean first,

   Hope this helps

   Ian
7. 

   Nicola De-Haan

   January 30, 2012 at 7:49 pm

   Hi Ian,
   Looking at the tiles more closely they do seem to have gone a bit grey and cloudy – is this acid etching?
   I got a quite off a company and just to grind the few tiles which are the worst – 10 of them they quoted £550.00

   Can you suggest an alkaline cleaner I could buy?

   Many thanks 🙂
8. 

   Ian Taylor

   February 6, 2012 at 10:41 am

   Hi Nicola,

   If they are dulling down and going grey, then that is a sure fire sign that they could be a basalt, this would be indicitive of acid etching. It is also possible that a build up of alkaline detergent could also create this dull effect, but by leaving a dull patina on top rahter than actually dulling ths stone. This would be removable with a good clean with an alkaline cleaner (as long as you rinse well) and/or an abrasive such as Microscrub.

   However, my gut feeling is for the former, based on what you have said. If this is the case, then an alkaline cleaner will not help (apart from cleaning it well). I am afrad the only way to fix acid etching is re grinding/polishing, and I have to say that with basalt, it is not always 100% possible, although it can help and improve the look.

   An enhancing sealer can also help, but I am reluctant to advise this as any previous sealer may cause problems

   The other thing to point out is that it is hard to just re surface 10 individual tiles, normally the whole floor would have to be done for a uniform finish.

   a good alkaline cleaner for on going cleaning would be Xtreme Clean by All For Stone, if it is not on the site yet, you could call them

   Hope this helps

   Ian
9. 

   L.Spink

   May 28, 2012 at 7:02 pm

   Hi
   After i have cleaned my granite no matter what cleaner i use after i have polished it off when you walk on it it leaves foot prints what can i do.
   Linda
10. 

    Ian Taylor

    May 30, 2012 at 12:03 pm

    Hi Linda,

    This is hard to advise, it could just be that the polished surface is susceptible to this – imagine if you were to walk barefoot or in stocking feet on glass, you would leave marks – just like we leave finger-prints on any high shine surface.

    However it could also be that the is some kind of residue on the stone. Fore example, there could be residue from the sealer if one was used, or, it could be that what ever product is being used to clean the floor, especially if you are not rinsing, is leaving a build up/residue.eEither way this can build up a sticky surface that is hard to see at first, and cannot be felt, but it is there sufficiently to grab hold of tiny particles from our feet/shoes etc when we walk on it.

    Suggest giving the floor a good wash, but, make sure to mop up the water, then wring out the mop and apply fresh, clean water to ‘rinse’ the floor, then mop up again. then finally, take an old towel and dry the floor, (buff it dry). See if this makes a difference, if it does, then adjust your cleaning regime so that you include a rinse and buff.

    Hope this helps

    Ian
11. 

    ifeoluwa

    September 8, 2012 at 6:24 am

    can olive oil be use for polishing a stone floor to make it shine
12. 

    Ian Taylor

    September 11, 2012 at 1:18 pm

    You know I have never really tried using olive oil in this way, apart from using it to briefly darken something – just to sow what an enhancing sealer will look like – not for anything permanent. Oils have been used on stone but I suspect there are several things wrong with using Olive oil:

    First of all, I doubt it will ever dry hard enough to ‘polish’ like a floor wax. It may well appear to shine when buffed – but all you will be doing is making the floor glisten with wet oil.

    Secondly, in order for it to ‘shine’ at all it means leaving oil on the surface, as I think it will stay wet/mobile it will create a massive potential slip-fall hazard. And if it should get wet with water then ……

    Also I just don’t think it will last any length of time; it is a food grade product, it will decompose (rot/go off if you like). It may attract and harbour bacteria, this will make it look and smell bad, and also get sticky, which will attract more dirt.

    It will quickly and naturally, fade, so any colouring effect it has will be short lived

    regular cleaning with even mild detergents will remove it

    You would be better off in my opinion with an enhancing sealer for colour or a topical sealer if the sheen/shine is the important factor.

    Hope this helps

    Ian
13. 

    Ann

    February 20, 2013 at 12:25 pm

    We have made the mistake of letting Cillit Bang cleaner get on to our granite tiled floor we now have white stains everywhere is there anything that can be done to remove these stains in the tile?
14. 

    Ian Taylor

    February 21, 2013 at 5:54 pm

    Hi Ann,

    Unfortunately you could have a bit of a problem. First of all, most granite is not acid sensitive so yo have probably actually got a Basalt, or have been very unfortunate to have got one of the few granites that is acid sensitive (is is black?).

    If it is a black ‘basalt’ it can be very difficult to fix, polishing the white marks out is not easy as the acid (in the cillit bang) tends to go deep and bleach the colour out. If the stone has not been sealed then it might be possible to use an enhancing sealer to darken the patches down again.

    Can you send me some pictures, it might help – contact me via the contact us form – and ignore any error messages that the recaptcha form gives you – I need to fix that but the messages do get through, I will then reply and you will be able to email me directly

    Regards

    Ian
15. 

    Vincent

    February 24, 2013 at 4:28 pm

    I have a wild west granite (from Brazil I believe) worktop. I had put a couple of bottles of acid on it, used for cleaning expresso machines. Unfortunately, the bottoms of the bottles were not dry and has left a crescent mark on it, which is only visible when wet. When you run your finger over the wet surface, you know when you have reached it as it feels different; it also seems to ‘attract’ water. I suspect it has burned away the protective chemical film that was originally put on. Am I correct? Do I need to neutralise the area? Using what – sodium bicarbonate paste? Then repply protective chemical film and all is good?
16. 

    Ian Taylor

    February 25, 2013 at 2:57 pm

    Hi Vincent,

    I think it is worse than you suspect if I am honest. I think it is less likely to be the acid damaging the coating (there was probably an impregnating sealer applied) than the granite itself – some granites have a small amount of calcium-type mineral within the fine matrix that surrounds the crystals, some are actually not even granite, but some other igneous rock like basalt. I am not familiar with the exact geology of your stone but descaling acids are usually strong, and based on HCL or similar and if it is visible when wet/attracting water and feels different when touched (rougher) then it sounds like the stone has been damaged – it gets darker when wet as the fine polished surface has been eroded away to reveal a coarser surface that lets water in more quickly (as well as the stone being eroded, any sealer that was there, attached to the stone, will have also gone as well).

    It might be that the surface can be locally re polished – suggest you contact your supplier – they are often equipped these days to effect small repairs. then get the same sealer to top up the repair area

    Hope this helps

    Ian
17. 

    paul

    March 31, 2013 at 8:39 pm

    hi my marble table has wine stains all over it can i get something to sort this out i am in deep trouble can you help
18. 

    Ian Taylor

    April 2, 2013 at 11:59 am

    Hi Paul,

    OK you may have two issues, staining and etching.

    Wine has an acidic nature, and acids will etch (eat into ) the surface of a marble. Without the acidic content, the red colour from the wine (assuming it is red wine) would actually take quite a while to penetrate the stone to any degree, if it is a polished marble, however the acid essentially burns its way through the polished surface of the marble, and in doing so, as well as removing the shine, it also opens up the pores of the stone to more easily receive the stain. If the stone is unpolished then the staining would happen sooner, but the etching would be less noticeable.

    As it is a table I am going to assume it is polished, and the more polished the stone, the more noticeable any etching. So, you may have what appear to be deep stains, you may well be able to remove these with a deep cleaner and or a poultice. However once you have removed the stains, you may find that when dry the marble has now lost its shine, and with it, any depth of colour. This can be repaired, but it will need re-polishing and this may be something that would best be accomplished by a professional.

    You appear to be in Ireland, I have a good contact there who may be able to help, send me a message via th contact page and I will put you in touch.

    Hope this helps
    Ian
19. 

    Ashley

    June 17, 2014 at 10:43 pm

    Hi Ian my friend in Thailand has a bar in his house and the counter is black polished marble which has become faded where he tends to pour drinks and has finger print marks also.
    His friend in England brought over some sort of marble polish which did nothing so I was thinking maybe car cutting polish on a buffer pad attached to a drill may fix this what do you think? or is there anything that can be done?
20. 

    Ian Taylor

    June 27, 2014 at 10:36 am

    Hi Ashley,

    Black marble is notoriously tricky. For a start much of the black ‘marble’ used in this way is actually more like a very dense limestone, not that that matters at all – it is a natural stone that is black and ‘just about’ hard enough to take a mechanical polish.

    The problem is that compared to some marbles it is relatively soft. So it looses its shine comparatively easily. The dulling that your friend is experiencing though is down to acid etching – the alcohol and acidic fruit-juices all eat away at the finer calcium particles and have the same effect on the fine, polished surface of marble as sand blasting does on concrete. Etching, and ‘roughing up’ the surface in this way (although it may not feel rough to the touch) also ‘kills’ the colour of polished marble, this is normally re instated after polishing it again. However, one other common issue with black marbles (and green) is that when it is etched, sometimes the colour can be bleached out semi permanently. It can be re-polished though. The marble polish the other guy brought over may be just a simple cream polish (like a wax polish for a car) its only function to add a wax coating which might bring a temporary artificial shine. But it won’t create a mechanical (and lasting) polish.

    The term ‘polish’ can be misleading, it can mean adding wax as above, but most of the time when we talk about polishing we are talking about the mechanical (and sometimes chemical) alteration of the stone – grinding it flat and smooth with progressively finer abrasives – so like sanding timber with finer and finer sand paper until the desired fineness is achieved.

    So what can you do?

    There are other polishing creams available that are actually mild re-crystallizing creams – they utilize and acid and abrasive powder and through a combination of mechanical and chemical process, alter the surface of the stone and cause it to re-crystallize as a slightly different compound that is harder and shines to a higher degree.

    Your cream polish may have been one of these, and it may not have worked, this may be because your black marble may not react all that well to this type of system. If your polish was just a wax polish, then it may be worth trying a crystallizing polish.

    Bear in mind crystallizers are not universally popular in our industry as they can, over time damage the surface – they are a quick fix in this instance and may help your friend but should not be used over and over again.

    At some point, and that time may already have been reached, your friend will have to have the surface of his marble re-ground using proper abrasives, like diamonds.

    If is is only a small bar, a set of ‘hand diamond pads’ can be bought quite inexpensively now, they come colour coded for the different grades (start course and work up to fine) the process is just ‘sand’ the counter top keeping the pad wet by dipping it in clean water every so often, then move up to next pad etc.

    This is less effective in my experience on black marbles and he may not be able to get all of the colour restored, but he should be able to get rid of the etch marks and bring back a uniform even shine.

    I would then add a wax-type marble counter-top polish and use this regularly – to give a small degree of surface protection from the inievitable ongoing spills- – it is easier to maintain the wax on the top than to have to keep re surfacing the marble itself

    hope this helps

    Ian
21. 

    Joan

    December 11, 2014 at 3:14 pm

    Hi,

    I have this floor in the toilett which by specification is supposed to be compressed (conglomerated) marble in honed finishing. when we first got the place it got stained with shoes soles and the normal dirt from a moving day, then when I tried to wash it, to my horror I noticed that the stains don’t go away, I also then noticed how porous the material was (it absorbs water and change color from very light grey to medium grey in contact with water) then I started to research on the material and everybody seems to mention that compressed marble is easy to clean and stain resistant etc, but basically what i have is a very porous floor that stains with normal shoes horribly and the stains cannot be removed. I tried everything I could that wouldn’t damage natural real marble, so marble soap, light detergent, organic expensive floor cleaner and nothing seems to work, the stains are there and while cleaning I create even more stains with my slippers. is there a way to clean compressed honed marble or should i just stain the crap out of it until it looks intentional?
22. 

    Ian Taylor

    December 19, 2014 at 10:38 am

    Hi Joan, for the shoe marks you could try a mild abrasive cleaner that won’t scracth the marble. I would then look to seal the floor with an impregnating sealer so that it is less absorbent and will stain less in the future.

    As you appear to be in Singapore, you could contact a friend of mince at http://www.floormedics.com.sg/ – Vincent Lee there should be able to help.

    hope this helps

    Ian
23. 

    Tanya

    April 18, 2015 at 9:23 pm

    Hello

    I have a lovely basalt work surface in my kitchen, however it has recently got a few brown marks on it. Is there a way I can remove these? Unfortunately I don’t know what has caused them.

    thank you

    Tanya
24. 

    Ian Taylor

    April 20, 2015 at 6:15 pm

    Hi Tanya,

    Very hard to say when we do not know what the marks are or what caused them, Could be as innocent as tea stains, in which case try a high alkaline deep cleaner. Can you ‘feel’ the marks or do they seem to be in or under the surface? Maybe a gentle abrasive cleaner like All for Stone Microscrub will help but if it is under the surface then it can be very difficult. Basalt can be a tricky stone, it can often be susceptible to attack from acids – (and that can be lemon juice, orange juice, wine, coffee etc). Some acids will leave a white mark, but others can leave a coloured one such as the brown marks you are seeing. It depends on what acidic compounds are reacting with what minerals in the stone. Occasionally there can be iron bearing minerals in this type of stone and under the right conditions they can react with water and the air, and oxidize, to form basically, a type of rust. This can be deep in the stone and it can be impossible to remove.

    Do you have any pictures? You can contact me via the contact us page, then I can replay with my email address so you could send pictures that way – it sometimes helps for me to see the problem.

    Hope that helps

    Ian
25. 

    Angela

    January 22, 2016 at 8:22 am

    Hi Ian

    I have liquid shoe polish stain on my quartz kitchen work top, what can I use to remove the stain? The quartz is a compaq lactea finish.

    Looking forward to your suggestions.
26. 

    Ian Taylor

    February 12, 2016 at 9:14 am

    Oh Dear, apologies for the late replay – I did not see this.

    Well, as some polish will contain some wax I would try an alkaline cleaner first, with warm water, but you may need to go to a solvent. You might find that you can get the majority of the stain off and that the quartz itself being resin based, has not actually stained.

    Good luck

    Ian
27. 

    Ros

    February 26, 2016 at 8:13 am

    Hi. We have original slate flagstones (1869) in the hallway of our house. Alot of the slates have dull and pale patches where the surface has split and broken off. These patches are very porous and despite using the appropriate cleaning and sealing products, still remain light in colour and dull. How can we restore the slates to a more evenly coloured condition please?
28. 

    Ian Taylor

    February 26, 2016 at 9:09 am

    Hi,

    Slate and other stone’s finish is a key part of the shade and colour etc. The natural finish of freshly split and exposed slate, where flakes have come off to reveal a fresh bit of surface, will be different to the long-exposed surface. The top finis of your slate may well have been rubbed smooth/polished at the time but it has certainly been ‘polished’ through wear if it has been down since 1869. It has also most likely been exposed to all manor of cleaners and treatments, natural and synthetic (including oils and waxes) i its lifetime.

    So, it has ‘aged’ significantly as a result – where ever you get flakes coming off that take this surface away and reveal fresh parts of the stone it is going to be different, even if it feels smooth, it will be more textured and rough – and this accounts for the relative dullness, the colour difference is due to its pristine, untainted life so far.

    There is not much you can do really as trying to clean it won’t help – it is not yet dirty, the rest of the floor is, relatively speaking of course. And sealing it wont help either. There is a chance that using an enhancing sealer may darken those spots and bring them into a closer shade but you would have to try to just do the spots and it will still not match 100%, and of course it wont alter the dullness.

    I see two courses of action, mask for now with a sealer and trust that over time as the new patches begin to see a it of life, they will slowly start to come closer in appearance to the rest of the floor, or, get a specialist flooring contractor in to test and advise if it can be restored they would have to regrind the floor, all of it past the exiting patina, to get to a point where all the floor was freshly exposed, they could then maybe come back up the grades of abrasive and make the finish finer, then a sealer could be added at the end – it will look newer than it does now, but not as new as the bare dull patches, it should at least be uniform – but take professional advice there may be reasons with a floor that old, why attempting this may not be a good idea, condition of the subfloor etc.

    Hope this helps

    Ian
29. 

    Ros

    February 26, 2016 at 10:51 am

    Thank you Ian, your explanation and advice is most helpful.
    Ros
30. 

    caroline allen

    March 17, 2016 at 6:23 pm

    Hi Ian, I know that ceramic floor tiles do not normally get etched but my entire bathroom floor has been etched and looks terrible. I was my own fault. I applied a polish which then peeled and to remove it I used polish remover which then caused the etching of the floor tiles. They should be a plain matt black finish. I read somewhere that using a car cutting compound was the only way to restore the floor to a single colour. Is this true? and if so what type of cutting compound is best and how should it be applied?
    Any advice gratefully received as this is a brand new floor and I do not have the money to replace it
31. 

    Ian Taylor

    March 18, 2016 at 11:26 am

    Hi Caroline,

    From what you have said I doubt you have etched the tiles. Etching occurs when a corrosive substance actually burns/damages the surface of the ceramic/glaze. Most strippers are solvent based and I would to expect them to have done any damage to a ceramic tile. More likely you have done a partial job of stripping and the colour differences you are seeing are actually residual deposits of the now damaged sealer/coating. Try reapplying the stripper another 1 or two times, it can be simply that it takes several attempts to break through the total thickness of a coating like this, and the first one just takes the top off, making it appear dull and whitish for example.

    Hope this helps

    Ian
32. 

    Olivia Lynan

    May 20, 2016 at 10:15 am

    Hi Ian,

    I am hoping you can help me – I had Sea Grey polished granite worktops installed last week, and 5 days later I had a big grease stain and 3 white rings (which I think could be etch marks?) I did a poultice which got rid of the grease (soaked the area with a wet tea towel then sprinkled with dry cement) but the white rings are still there. Any suggestions?

    Thank you,
    Olivia
33. 

    Ian Taylor

    May 20, 2016 at 11:35 am

    Hi Olivia,

    OK first of all I don’t know the granite, a quick search on google did not really help either. If it is a polished granite and it has been sealed then I would have thought removing the grease would have been quite easy. If not then sure a poultice can work – never used cement and water to make one though – that does not sound like a great idea to me to be honest – as you are making a wet cement that could stick, and stain in itself. There are various clays and poultice materials out there for this – but it seems to have worked with no ill effect so great – I am not recommending that other people try this though.

    Regarding the ‘etch marks’ they certainly sound like etch marks from what you say. The thing is not all commercially available ‘granite’s’ are technically actually granite, they can be other stones, with very similar origins and qualities but some, like basalts can etch quite easily, most (not all) true granites are very resistant to acid attack. Stone etches like this when there is something in its make-up that is sensitive to acids, usually some form of calcium in the fine matrix that surrounds the larger crystals of the various minerals that make up the stone. The sensitive parts will react with acids, found in normal household liquids including cleaners, fruit juices and wine etc. A very common cause is wine glasses being left on the counter with drips of wine accumulating at the base – hence the rings. The reason for the white rings is that where the stone is etched, it has essentially had the calcium, or other acid sensitive material dissolved away, and in the process this roughens up the surface, altering how light is reflected and therefore for the colour and shine is lightened and dulled.

    With all over calcium based stones like marble for example, rectifying the problem usually involves repolishing the surface – so, grinding away the now rougher part and then sanding it smoother again to get that ultra polished surface back – with it comes back the colour and shine. This repolishing can be done mechanically and or chemically depending on the situation. It is much harder though for granites as you only want to repolish the dulled part and the undamaged surrounding crystals make accessing the finer damaged matrix harder.

    This means that some of the chemical pastes and ‘quick repolishing’ remedies that are available for marble don’t work on this type of granite.

    So you may have to get a stone professional in to re surface the stone and that would really require him/her doing most if not all of the surface to get a good finish.

    However one thing you might try is this, does the etch mark darken to the point that it becomes invisible when it is wet? – if so then applying an enhancing sealer may help – it might at least mas the issue. Of the work top itself has not been sealed before then you would have to seal the whole thing – and it may darken the colour significantly which you may or may not like.

    Hope that has helped a little

    Ian
34. 

    Rana

    June 24, 2017 at 6:17 pm

    Hi i have used by mistake my granite natural wash basin counter stone in taski suma de scale spary on the granitr counter stone and not washed properlly after some time that stone clour was white visable type again i was washed it it is some better but granite stone were white visable please sugges me for natural clour recome.
35. 

    Ian Taylor

    July 6, 2017 at 11:24 am

    Hi,

    OK, Don’t know the product, or which granite you have but, the de scale product is clearly acidic and some (not all) granites can be etched by acids. Etching is damage, not staining, The white marks are where acid sensitive parts of the granite (or the fine matrix between the granite crystals) are burned by the acid this makes them rougher textured, and reflect light /scatter it, in a different way, it moistly likely looks better when you wet it, but goes white again when you dry it. Unlike marble, which can sometimes be re-surfaced with the right acidic polishing products, granite tends to be much harder to fix. Typically you will need to either try to mask it with an enhancing sealer (one that makes the granite have a permanent wet look) or all a stone professional to see if they can re grind/re polish it mechanically.

    Hope this helps

    Ian
36. 

    Naomi Preston

    August 22, 2017 at 4:25 pm

    I’ve just had my oven cleaned and the guy was getting spay all over the creamy grey granite I asked him to wipe it off and avoid the granite he said no its no problem won’t harm. But when he had gone I noticed patches have gone a dull grey-black. I called him back and he said his products don’t do that and it must have been there before.- It definitely wasn’t. I’m going to find out what he used was this may help. Any ideas ? Thank you
37. 

    Ian Taylor

    August 24, 2017 at 9:16 am

    Hi Naomi,

    Sorry to hear this. OK, I am not 1oo% certain here but, most professional oven cleaning chemicals are very strong caustic solutions (sodium hydroxide) so for him to say ‘it won’t harm’ as a blanket statement is a little careless I feel. Such chemicals can be extremely damaging to certain materials (and people). The question is, ‘will it harm granite’. The answer is – it might. It depends on a few things, the first one to check out is has your granite had any kind of coating or surface treatment? By this I mean either an impregnating sealer applied during or subsequent to installation, (including any wax or silicone coating /polish applied on top) or some kind of treatment (wax, silicone, resin etc) applied at the factory before delivery. It is very possible that the oven cleaner could damage/etch. lighten or partially strip some of these treatments leaving a patchy/dull appearance. You would need to check with your granite supplier to find out exactly what, if any treatments have been applied, right from the factory(which may even be in China) through any fabrication companies right up to the final installation at your premises. IF you are able to find out, you may or may not be able to ‘top it up’ and restore the look.

    There is also the possibility that the granite itself may have been etched in some way by the cleaner we see this a lot with darker granites, imported from China, when subjected to ‘acidic’ cleaners – less so with lighter coloured ones and caustic cleaners – but I believe it is possible. IF this is the case then what tends to happen is that the chemical etches (which means removes /reacts with and dissolves) the very fine particles in the surface – having the effect of of rubbing smooth wood with rough sandpaper – thus roughening up the surface – the net effect on polished stone is that the surface looks more dull and less colourful.

    Does the colour temporarily return when the granite is wet? if so this can also indicate etching.

    If you do have this issue then you would have to seek the advice of the granite installer or a professional stone restoration company to enquire about work top resurfaced.

    One last possibility is that there is just a deposit (dried on stubborn trace residues of the cleaner and any dissolved grime it has within it) left boded to the surface – I feel that this is less likely given your description of the dull/discoloration but it is worth exploring. Try using a white nylon scouring pad with some water, see if it makes any difference.

    Hope that helps

    Ian
38. 

    Chrissy

    October 3, 2021 at 1:17 pm

    Unfortunately we left a tray of strawberries on our grey shiny natural stone kitchen worktop and the juice seeped on to the workshop. As I did not see this for a while it has left an imprint of the tray on the worktop. I have tried making a paste from bicarbonate soda and warm water and leaving for a few hours but the marks have not gone. As the property is rented this is a concern so wondered if you could recommend other solution to remove citric stains from a natural stone kitchen work top
39. 

    Ian Taylor

    October 11, 2021 at 11:41 am

    Hi, OK, this sounds like it could be more of an etch than a stain. you don’t say what the grey shiny stone is? is it slate or polished marble? or granite? This could be important. Worst case, it is marble, and the acidic juice has etched (i.e burned away very tiny particles from the surface) this makes the surface lose its shine and opens it up to make it slightly easier to stain – so you could well have a stain but that may not be the main issue.

    The stain itself might be removed with some dilute household bleach, left on for a little while then rinsing, the etch, however, if there is one, would require repolishing.

    Think of an etch in stone as a surface scratch in timber, the only way to remove it is to sand down the surrounding surface until you get to the level of the scratch then use fine sandpaper to put the smooth surface back. It is the same for stone, there are kits on the market that let you carry out DIY ‘local’ repairs, might be worth looking into.

    Hope that helps

    Ian