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Cleaning Slate – Expert Advice on Cleaning Slate and Slate Floors – Part 2 »

Some detailed instructions with regard to cleaning slate floors:

If the slate floor is adversely covered in cement or grout residue:

1. Use water to pre-wet the floor.

2. Apply some phosphoric acid-type cleaner solution to the floor – mixed with 1 part cleaner to 5 parts water to begin. (You can use a stronger mix if required). **PLEASE NOTE: Always conduct a small test on a relatively inconspicuous section of the floor first, before you begin.

3. Leave the cleaner to dwell on the floor for a few minutes

4. Agitate the floor and cleaning solution with a scrubbing brush (nylon bristle and not metal).

5. Soak up the cleaning solution remaining on the floor. Rinse well with fresh water, agitating again so you can get rid of any residual acid cleaner.

6. Make an assessment of the floor at this stage. You may need to apply an additional treatment of the cleaner.

If your slate floor only requires routine cleaning we would recommend a neutral cleaner like Ezy Clean by All for Stone – this is a mild cleaner and is safe and suitable for cleaning slate on a regular basis.

For more intensive slate cleaning, where the dirt is not mineral- based, we would recommend the use of a heavy-duty alkaline cleaner like Xtreme Clean. This a powerful cleaner and degreasing solution. When applied to the floor, leave to dwell for between 5 and 15 minutes, depending on how bad the contamination. Then agitate by scrubbing with a nylon or natural bristle scrubbing brush. Clean up remaining the dirty solution and rinse well with clean water.

The critical elements here are the dwell time and the rinsing. Alkaline-cleaning solutions need time to work. Once you have “extracted” the dirt from the floor it will be suspended in the solution so you absolutely must remove it – on no account leave it to dry naturally.

Copyright Ian Taylor and The Tile and Stone, 2013. See copyright notice above.


  1. Hi
    I hope you can help me. A couple of months ago we purchase a piece of slate to place under our pot belly stove, recently some diesel was spilt on the front of the slate, can you offer an advice on how I might attempt to remove it please?
    Many thanks in anticipation Amanda

  2. Hi Amanda,

    OK you could try a poultice. If the slate is very porous then I would first try cleaning with a high alkaline product like Heavy Duty Tile and Grout Cleaner; fist I would pre-wet the slate, all around the stain, BUT NOT THE STAIN ITSELF. This is to get warm water in around and possibly under the stain, I would do this to try to prevent the de-greasing chemical from pushing the stain further in. Then apply your cleaner to the stain, leave it for 10 to 15 minutes but keep it/everything wet, then scrub lightly and use an absorbent cloth to take away the liquid. Rinse and dry.

    If this does not work, try a poultice: mix some Heavy Duty Tile and Grout Cleaner 50:50 with water. Then use this solution to make up a thin paste with Aqua Mix Poultice Powder, mix to a creamy consistency. Pour the poultice mixture over the stain, covering an area approximately 20% bigger than the stain. It will be about 1 cm thick. Now, cover the poultice with some plastic film, put a couple of holes in it and leave it 24 to 48 hours. If this is on a vertical face, then first make a ‘pocket’ with the poly-film and some tape, then our the poultice into it, seal the top but leave some space for drying.

    Remove the no dry poultice carefully and inspect, if it the stain has gone then fine, if it looks worse, this is good – it means the stain is being drawn to the surface- just repeat the process.

    It looks like you are in Aus? – you can get these product ( and some good advice) from

    Hope that helps


  3. Brian ROBINSON

    August 9, 2011 at 5:06 pm

    How can I remove White paint. From external slate windowsills.Blobs I can scrape off but most are smudges where attempts have been made to clean up.Beautiful material utterly spoilt.

  4. Hi Brian,

    Really you need a paint stripper, I would suggest one deisgned for use on stone like Sealer & Coating remover, leave it dwell for a while then scrub off. You could also add a little nanoscrub or a poultice powder to help absorb it off once it has been cheimcally disolved. Make sure to rinse well after wards.

    Hope that helps

  5. Hi,

    I was wondering if you could help me. We’ve currently got natural grey slate in our kitchen. Unfortunately, there has been some paint spilt on the kitchen floor but some of of it has been removed but it still looks very dull and lost its sheen.

    I read the comment above but I am still worried that our slate floor is porous and will stain the slate rather than clean it.

    I was wondering if you can recommend me a product that will remove the thin layer of paint that has been left on the slate.



  6. I have a slate stone patio and a walkway entrance leading to the front of my house. It is dirty and uneven in its color. What can I clean it with and what solution can I seal it with. How often do I need to put a sealer on it. Also, there are some paint marks and oil stains on it, too. I appreciate any advice that you can give me.

  7. Hi Lew,

    OK, for an external deep-clean I would use a high powered Alkaline cleaner that is designed for stone.

    If it is a large area I would borrow or hire a rotary cleaner with a medium nylon brush head. If the slart is very absorbant, pre-wet the floor with water, then apply your mixed cleaning solution and leave it to dwell for 15 minutes or longer, (keeping it wet though, with more cleaner). Then scrub with the machine, really work the brush into the uneven parts of the slate and don’t forget to work on the joints.

    Now rinse – with plenty of clean, fresh water, a wet vac may not be practical outside with uneven floors, so maybe you can use a hose or pressure washer to rinse away the now dirty cleaning solution, go over the floor again with the scrub brush while rinsiing also to make sure you get all residue up and off the floor.

    Once you have done this, the floor should be a whole lot cleaner, and you may find that much of the paint splashes have come clean in any case, for any remaining spot stains like this, get a paint stripper, be careful and try to get one from a tile/stone shop desighed for the job (there are some slow acting, non-methyl chloride products that work great.) You can use any paint stripper but some, like turps and white spirit can leave an oily stain themselves.

    When thourouthly dry (wait a few days – depending on where you are) you can seal it. You have a couple of choices. Usually a coating sealer (that leaves a nice sheen) is not an option outside – due to the harsher environment, they tend not to last too long and become too much of a chore to keep in good condition. So most people opt for a good quality impregnating sealer. They won’t give a sheen but but will leave a natural finish, you can choose between a natural or colour enhancning version which would bring out the colours but not add a coating or shine.

    Hope this helps


  8. Hi Denise,

    a lot of slate problems this week –

    OK, you need a good stripper I suggest sealr an coating remover, no longer being brought intot he UK but there are still ample stocks at All For Stone – see ad link – suggest you give them a call they can also advise you how to use it.

    Hope this helps


  9. Hi Ian,
    I am so pleased to have come across your article and am looking for some advice regarding our honed slate hearth.

    One of the kids spilt their cup of milk over much of the hearth, and we didn’t know about it until the next day. We found to our horror after wiping it up that we are left with the staines!

    Can you offer us any hope or advice?

  10. Hi Marc,

    This may not be too difficult, it depends on the slate, but most hearths are typically from good quality, quite dense slate, especially if they are honed. So, I am assuming that your slate is not too porous. This means that you may only have surface stains. Milk will leave fatty/oily stains and so you need to try an alkaline degreaser. First pre wet the area with warm water, then mix an alkaline cleaner with warm water and add it to the staine, allow it to dwell for about 15 minutes (don’t let it dry out) then scrub with a white nylon scrub pad.
    Wipe up the cleaning solution, then rinse with clean water, wipe up and dry with a towel.

    I this does not work, try a poultice

    Kind regards


  11. Hi
    A couple of years ago my husband laid a natural slate floor in our kitchen it looked lovely – but then he sealed it with wood sealer I’m really not sure why. The result is we now have a horrid grimey brownish coating to the tiles. The floor is very difficult to clean, takes lots of effort and really dosent look any cleaner.Please help.

  12. Hi Linda,

    OK, thse types of sealer are more like a varnish and don’t breath properly in general. after a while they get grubby and can even peel. They can also harden, and go dark or yellow/broan in colour as they age. My only suggestion would be to strip it off and start again. They can be quite tough to remove, needing a strong stripper and more than one application. I would suggest trying something like Sealer and Coating Remover which you can get from All For Stone (see ad on right).

    see the stripping a coting sealer post on the blog.

    I think that you may be pleasantly suprised at what is beneath the varnish, when clean and dry consider using a product like Seal & Finish Low Sheen – low maintenance coating sealer, will give a slight sheen and will need topping up in due course but much nicer to care for than the type pf sealer you have at the moment.

    hope that helps


  13. Hello. Can you help us, we had a Brazilian slate floor laid it was grouted before they sealed it. And it never looks clean after washing paw prints etc never goes away I can we rectify this.
    Thank you.

  14. Hi Wally,

    You are going to have to go back to the surface of the slate. If it has been sealed with a topical or coating sealer (which is now over the grout residue) then you will first need to strip that back with something like Sealer and coating sealer or equivalent.

    Then, if there is still some grout residie (it may come off as a result of the stripping opperation if you are lucky) you will need a phosphoric acid based cleaner to remove the grout residue, and this may take several goes. Do not be tempted to try to speed this up by going for a brick acid – that can and often does, create more problems than it creates.

    Hope this helps


  15. Hi Ian,

    I am hoping you can help. We have a smooth (not riven) slate in our kitchen and hall. It has not been looked after very well and I am pretty sure the majority of the seal has come off, we have certainly never done anything with it in 8 years so you can imagine it is a bit of a state.

    So far I have scrubbed it with a nylon scourer using a slate cleaner. It is looking much better but there are parts that look like they have a sort of white haze on them which I can’t get off it seems to be at the edges, is this the old sealant do you think? I have no idea what was used to originally seal the tiles, I am loath to reseal without getting the floor totally clean. Many thanks.

  16. Hi Carole,

    OK, the white at the edges could be one of 3 things:

    Salt efflorescence – mineral deposits from the grout and or subfloor, grout is porous, the slate is not very porous, so any moisture trying to get out of the system, will come through the grout, not the slate, as moiture comes out of the grout, any disolved minerals that may be in the moisture will be brought to the surface where they will re form as crystals. If this is the case, it would temprarily disapear, or face at least when wet, only to become visible again when dry- a simple test, if you think you have this, a very mild phosphoric based acid cleaner, diluted with water, (nothing stronger like brick acid) will help.

    Grut residue – ot could be the remnants of uncleaned grout residue from the installation, if it appears to have got worse recently, then the above is more likely, if it has be there unchanged for years then it could be grout residue. – Again same traement as above, mild acid clean.

    It could also, as per your suggeetion, be the last traces of a topical sealer, but I would expect to see traces in other areas, like in crevices in the stone face, not just at the edges, even a non-riven slate may have some unduations and so some low spots that would protect the sealer from wear. It it was a sealer residue you would need a stripper to remove it.

    Hope this helps


  17. Hey Ian,
    You seem to know your stuff regarding slate and stones, so maybe you would help me repair a stupid mistake I made. I sprayed my new smooth slate hearth, which isnt sealed, with cilit bang (non bleach) which contains formic and sulphamic acids. I’m left with horrible white patches all over where the spray hit. I’m thinking a strong alkaline cleaner and was wondering if lemon or vinegar with baking soda would be strong enough to do this or can you recommend a good propietary product and application method? Thanks, Martin.

  18. Hi Martin,

    OK, first of all, I am surprised that the acidic Cillit Bang has damaged the smooth slate, most slates sold for hearths are pretty old, grey, high quality types that tend not to be acid sensitive, so I would check that there is no film (cement, or other coating) on your slate that has been damaged by the cleaner. Or the cleaner could have dissolved some kind of contaminant and left a residue of that

    However, some slates can be sensitive to some acids and so it is not out of the question that you have some etching. IF this is the case, then you may be able to disguise it or mask it with a wax type coating, or an enhancing sealer (you do say that the sate has not been sealed with anything else, so an enhancer might well work). But, you will probably not be able to fix it without re honing the surface and that may require professional help.

    If it is acid etching, then the damage is done, trying to neutralise it now is pointless. Besides, vinegar and lemon juice are both acidic in any case, and mix either one of those with bicarbonate of soda, which is alkaline, and all you will do is create a spectacular bubble fest as the two react quite violently) it probably won’t harm the stone as the two things will fight each other and neutralise themselves but it won’t help much either and you will be left with the aftermath of the reaction – a hearth covered in a salt residue.

    I would try some Microscrub with a little water, if it is some kind of deposit from the cleaning product, this may help remove it. If it is etching, then it will do nothing but worth a try first in my opinion.

    Hope this helps


  19. hello! so wondering, based on some feedback, if i made a horrible choice by installing black slate for my shower and bathroom floor. i’ve been told it will be harder to clean then the white on white penny tile/grout that i had to replace due to the poorly installed cracking grout. am i going to hate this more then the filthy looking white tile/grout i had to rip out?? help! and what can i do besides sealing it? and is there a number one sealer you would recommend??


  20. Hi Butch, I must admit, I am not 100% sure what you mean by ‘white on white penny tile grout’

    If you are asking, will a slate wal and floor be harder to keep clean than a glazed white tile, then yes, it could be, but should not be a major problem.

    Sealing the slate is recommended as it will make the surface of the slate easier to keep clean. However, keeping the grout clean and like new has more to do with good management of the moisture in the shower area. A sealer will help keep contaminants at the surface, of both the grout and the stone, go for a good premium imprgnating sealer. THis will help reduce the amount of moisture able to get into the grout. ON top of this clean the tiles and grout reularly and also dry them down periodically, like once a week for sure. Doing this will keep moisture and contamination under control.

    Not sure if I answered your question so let me know if not


  21. Hi Ian I really hope you can help me. We have slate tiles outside and also around our swimming pool. On the tiles we have spots it looks like some of the layers of the tiles have come off. I dont know if it is caused by rain. we live in South Africa in Pretoria so we do get alot of rain. I have considered removing the tiles as it really does not look nice. Have you any suggestions plese.

  22. Hi Alme,

    This ‘flaking’ of some slates is perfectly normal, and should settle down after a while (once all the loose/friable material has come away). Slates come in all sorts of colours, and in many viarieties also, some much younger (geologically speaking) than others. Slates are metamorphic rocks, that means they ‘were’ somthing else before being changed (morphed) into slate. Basically most slates began as a sedimentary rock, laid down in layers (this layering of deposits is important in the formation of layers that can later flake away) of fine-grained materieral like clay, silt and mud etc. These sedimenatary rocks are then subjected to pressure and heat are compressed toghether. This compression, and folding and heat can cause things to break-down and or fuse, and also change and some minerals form cyrstals . This process takes time, lots of it, the longer the time taken (the older the slate) the less likely it will be flakey and have loose layers at the surface. Some of the more colourful slates I have seen coming from Africa can be quite flaky. Unless your slate is really friable, and almost more like a shale or mudstone than a slate, then once the loose parts have come away you should see the stone settle down.

    If it is rain water causing the delamination, then I would think the the stone is very soft and have easily split cleavage planes, the expansion and contraction of the slate as it gets wet, and dries out etc, along with extreme changes in temperature could have an ongoing weakening effect. Sealing the slates with a waterrepelling sealer will definatley help but it may not stop it altogether,

    My gut feeling is that if you cut-out the worst ones and replace (if they are that bad) and clean and seal them, you should see less of this happening.

    Hope his helps


  23. Hi Ian

    We’ve recently installed slate in the shower but we live in a very hard water area and although the slated has been sealed the water is marking the walls terribly! What do you suggest I use to remove the water marks? I was going to use a limescale remover but it said not to use on natural stone. I’d be grateful for your help!

    Many thanks

    Kelly Wright

  24. Hi Kelly,

    OK, hard water will leave marks on the slate, the fact that it has been sealed will only help prevent the deposit from getting deeper into the slate surface texture. Basically the hard water contains soluble minerals like calcium, this is deposited on the surface. (Sure, if you had a very porous stone, that was unsealed, more water would soak in and therefore the hard warder marks would go deeper and build up faster, where as on a slate, depending on how dense/porous it is, it will take longer, not go as deep, and where sealed, it should only be lying on the top). If your slate is very dense, and the sealer is a coating sealer then the clean up should be quite easy. If you have a more porous type slate, and you have a penetrating type sealer then it should still be much easier than had it not been sealed. The texture of the slate will also impact the cleaning, a smoother surface being easier to clean than a riven one.

    The other thing to watch out for is soap scum build up – this occurs when you have a reaction between soaps and the hard water – basically it is just another mineral deposit. Both hard water deposits and soap scum make a good base for mould and mildew to anchor themselves, so they can encourage their build-up too.

    The key with these is take action sooner rather than later (prevention is better than cure) the more they are allowed to build up, the harder they are to clean.

    A limescale remover will be based on a acid, you may be ok with this but I would check it is not based on HCL – or Hydrochloric acid as the fumes from this alone can damage anything metal, throughout your entire home. (These products are best used in external situations only).

    Instead get a product that is based on a phosphoric, or similar acid. But before that make sure your slate is not sensitive to acids – many are not; especially darker slates like Welsh Slate, some of the more colourful/exotic ones can be a little bit sensitive, where the colours are created by minerals such as iron for example (rusty/red/golden/brown colours).

    Also, and this is where a lot of people come unstuck, check any other surface that may come into contact with the cleaner by spalsh or run-off contact (stone shower tray, marble feature border, some chrome-plated plastic trims for example).

    Follow the instructions on the bottle and scrub well with a scrubbing brush. Rinse well with clean water (easy in a shower). Then, and this may surprise you, dry the walls down with a towel.

    Once clean, you will need to maintain the clean condition, you can do this by regularly drying down the walls ( I don’t mean after every shower, but say once per week, after the last person has showered, use a towel to rub the wall dry. This removes water, and with it any dissolved calcium and so prevents it from being left behind to harden as a deposit).

    Occasionally spray the walls with a very dilute version of the acid cleaner, lightly scrub then rinse and dry – again doing this little an often will be much easier than waiting for a hard water build-up and taking perhaps several goes at hard scrubbing.

    Occasional use of a micro-abrasive cleaner like Microscrub by All for Stone will also help.

    Hope this helps


  25. Hi Ian

    I was delighted to come across this forum as I could really use your advice.

    I have recently had slate flooring fitted in my kitchen. The tiler cleaned the floor and applied an impregnator.

    I returned from work to find a piece of cable on the wet tiles. I lifted the cable immediately however it has left a stain on the tiles.

    Any advice you can offer will be gratefully received.

    Kind regards

  26. Hi Lisa,

    It sounds as though the Tiler used a solvent based impregnator. The solvent may have partially dissolved the plastic coating on the cable. Now that the solvent has evaprated the plastic will have hardened again. You will need to use another solvent to try to break it down. One thing you could try is dab a bit more of the sealer that was used, clearly that solvent was powerful enough to melt the plastic. Let it sit for a few moments but then scrub, and wipe away. Do this a couple of times, to see if you can remove it. You will need to watch that it does not simply ‘thin’ the plastic and help it to dive into the stone – as I say you may need several applications until you have got rid of it. Using this method will at the same time, make sure that you are nost stripping the sealer out.

    If it does not work, then you may need a more powerful stripper, but you would probably need to reseal the affected area afterwards.

    Hope this helps


  27. The chimney breast above our polished slate mantlepiece has just been replastered. The plasterer used a glue on the existing plaster before putting on the top coat of plaster (I think he used a PVA glue?). However, there are smears of glue on the mantlepiece. What is the best way of removing these please?

  28. Hi, You could first try just water and a scrub pad, you might be surprised, polished slate is quite dense and impervious very often. To boos this try a micro-abrasive cleaner as an additive – something like microscrub. Failing this you may need a solvent paint stripper of some kind.

    Hope this helps


  29. Thanks Ian. Unfortunately things have moved on in the meantime. The person who just installed the mantelpiece (which caused the need for plastering) called by and said he would sort it. Seems he did, EXCEPT, he soaked the mantelpiecve (and the hearth that he installed) in Linseed oil. It is no very shiny (which we didn’t want) but, more worryingly, very sticky. Its been 3 days since he did it and its still sticky/tacky. Will it ever dry out?! Or do we need to do something to it? (Like removing some of the Linseed oil). Help!

  30. We have a sunroom with slate floor and a mid-sized area rug with thin foam padding. The room gets very cold in winter and very hot in summer. We recently discovered that because of the heat the padding had partially “melted” leaving imbedded residue on the slate. I’ve tried hot water/soap brushing and then gentle scraping with plastic scraper. Most but not all has been removed. Any suggestion on additional steps which I can take?

  31. Hi,

    Next thing I would try would be a micro abrasive cleaner, if you are in the USA, you should be able to get a product called Nanoscrub at the big box stores/tile stores. If that does not work, try the same but with a high alkaline cleaner. Give that ago and come back if no joy.

    Hope this helps


  32. Alan Blankenship

    July 11, 2012 at 6:34 am

    Hi Ian,
    I just put in a new wood stove hearth and had a contractor friend install the slate for me. He did a great job and used a Min-wax oil to seal and finish the slate, the colors really popped and it looked great for about two weeks. Now we have a lot of white streaking and white build-up in the valleys in the slate. Please help. Thank you, Alan

  33. H Alan,

    I am not completely sure but it would seem the (mineral spirit-thinned) wax has collected in the valleys and for some reason turned white – probably due to absorbing ambient moisture and it suggests that maybe there was a slight excess of the wax applied, or, sometimes it can appear to go into the slate, but can squeeze back out again later (particularly if there is a temperature change or a chance in humidity).

    You could try removing it with a little water and a scrub pad, then buff it dry with a terry towel – this way you may just get the excess off without taking too much away. If you have to resort to anything stronger like a stripper you will have to reapply the wax (only perhaps a bit thinner this time).

    Some slate is really not that porous, especially some of the greens and blacks, in many cases the wax will not really penetrate the slate it can adsorb rather than absorb – (that means kind of bond to the surface not soak into it).

    Hope this helps


  34. I have aquired a piece of slate salvaged from a pool table and have had a hearth cut from it. It seems very dusty and no mater how much I clean it it still seems dusty. How can I clean & seal this ready for my wood burner?

  35. Hi Janis,

    I am wondering why your slate is so dusty, even after several washes, perhaps it is a softer slate? – if so then I am not sure a sealer could help; sealers are not really designed to secure loose surfaces, or harden friable surfaces which dust that easy. Their job is to soak in and provide a degree of stain protection, rather than add any structural strength or cohesion.

    Usually the slate used in pool/snooker tables is of good quality, often coming from the Welsh slate mines.

    Is there perhaps a residue of the glue from the pool table cloth and that is the issue? Does it also dust easy on the reverse side (where presumably it has a rougher finish?).

    It may be possible to have the slate re-finished, (honed/semi-polished with diamond pads) this may eliminate the problem)

    It could just be that it needs a few more washes, scrubbing with a white emulsifying pad, after which it could settle down.
    Hope this helps


  36. Can anyone help we have recently moved into an old house which has many window sills made of slate. Over the years the house has been painted badly and there are lots of paint drips all over the sills can anyone recommend an easy way to remove the paint or is it possible to paint the sills with a slate coloured paint if paint removal is not possible.

  37. Hi Jeni,

    I guess you could paint the sills with any paint designed for masonry – but why?!! – I would first try to remove the paint drips, really you only need a paint stripper, try something like white spirits. If it works then after gice them a good clean with a a general alkaline cleaner and rinse well.

    Hope this helps

  38. Dear Ian

    Firstly many congratulations on your excellent site and the advice you give. It has made fascinating reading.

    I would appreciate your help with a problem we have with our terracotta tiles in our old farmhouse in France. About 15 years ago we replaced our old tiles with new, handmade tiles from the Gironde. These were lovingly oiled and waxed so you can imagine my horror when the house was closed up for a couple of weeks that summer after some very hot weather and we returned to find patches of black mould all over them. I partially cleaned this off on my hands and knees with a scourer but had to settle for the fact that this was now part of their ‘rustic charm’ as time did not allow me to do the whole house.

    We are now just about to replace the kitchen so I am going to strip off the old wax and start again there. The tiles are still black in patches, particularly under the furniture.

    Can you give me any advice on how I can remove this black mould safely. Is scouring them one by one the only method and what will that do to the face of the tiles. I have tried one with a very fine guage steel wool and that does seem to lift it but I am worried about damaging the tile surface further. Is there a chemical which would work?

    Your advice would be much appreciated

    Many thanks


  39. Hi Cheryl,

    First of all mould like this suggests some damp – so you might want to look into that. Of course, leaving a property locked up for several months at a time can cause this (perhaps there is a way to increase ventilation even when locked, vent bricks etc?)

    OK, you really should not just clean but also try to ill the mould, so some kind of detergent that contains an anti bacteria ingredient. You could even use some very dilute household bleach. Whatever you use it is likely to be high alkaline and necessitate a repair or top-up to the wax.

    Hope this helps


  40. Hi Ian,

    Great website and information! I have a kitchen that was tiled in slate 2 years ago. It was sealed at the time, but we neglected to reseal and now there are noticeable differences in the tile in areas that were covered by mats. We have red clay in our area and I would like to clean the slate and reseal. How can I remove the discoloration/stain caused by the red clay before I seal?

    Thanks! Sheri

  41. Hi Sheri

    If you are in California, try to seek out a product called Extreme by Aqua Mix – it was used for getting rid of the red clay staining. Depends how bad it is though, a good wash with a deep cleaner and a bit of nanoscrub may be enough.

    Hope this helps


  42. I have been advised to put a mixture of 50/50 boiled linseed oil and white spirits on my slate hearth to protect it without changing its colour etc. do you think this is a good idea

  43. Hi Rhiannon,

    I do not know what type of slate you have, if it is native to UK or northern Europe and dark in colour, it is most likely a very dense slate and I doubt much of the oil will penetrate, even at 50:50. If it is a more porous type then it could, however I would expect that in either case it will definitely darken the slate colour quite a bit – I would strongly advise doing a test on an off cut first. Also, it will need to be applied, allowed a few minutes to penetrate then buffed off to leave it dry and not ‘coated’

    Hope this helps

  44. Hi, not sure if you can help but any advise would be very welcome. We moved into our house and have inherited a fireplace with a black slate hearth which is polished, however there are a couple of large dull patches which after cleaning with warm soapy water do not shine, I have used slate oil to try and bring the shine back but no luck. Do we need to have it refinished or is there a DIY solution that we could try?

    Many thanks

  45. Hi Steph,

    it does sound like the actual finish has been either abraded or etched away – meaning that the fine, mechanically achieved polish has been physically taken off. If that is the case then the only way to put it back would be to re-finish.

    You could attempt to do it yourself with diamond hand pads like these:

    but you would need to try several different grades depending on how bad the etching is – and, you may have to do the whole piece, not just the patches for an even finish

    it is better, to get it done professionally as a pro would have appropriate machines to get a faster and more even finish than you might achieve by hand

    hope this helps


  46. Hi Ian,
    We came back from holiday to find that the power in our house had failed and the large upright freezer had completely defrosted, leaving a river of liquid (blood from meat mixed with juice from soft fruits and various sauces) which had congealed on the slate tiles in the kitchen. The liquid had pooled in the depressions in the rough surfaces of the tiles and though we were able to clean all the congealed liquid off, it has left a white film in these depressions which I have not been able to remove. Is this caused by the fruit acid and is there anything we can do to remove the film?

  47. Hi Linda,

    Sorry to hear of your misfortune. The white marks could be acid etching of the slate, although most slate is pretty resistant to it. It could be just residue of something, all those acidic juices and other things, there could have been some reaction between the different liquids and they white stuff is what is left behind when all the water has been removed.

    Ironically, it might be worth trying some kind of mild acidic cleaner to remove them – one based on phosphoric acid, not hydrochloric.

    Failing that try a micro abrasive cleaner like Microscrub

    If it is actually acid etching of the slate, you may need to investigate having it refinished, although if it is a riven surface that may not be possible.

    Hope this helps


  48. hi les have just fitted a
    slate hearth what can i use to polish to a nice finish before sealing it


  49. Hi John,

    I would not recommend any kind of chemical polish (i.e wax or silicone etc) before sealing, as this will prevent the sealer from getting in.

    Normally, for any stone, the degree of ‘shine’ is determined at the factory: different stones have different hardness’s, the harder the stone, there potentially higher the possible polish/shine that can be achieved. With slate, there is a lot of variety, some slates (like Welsh slate ) are very hard and will almost take a polish – (t it is actually a very fine honed finish- that means it is ground/rubbed very flat and smooth surface, that is starting to reflect light back with a hint of a shine)

    Some slates are so soft that only a rough hone can be achieved.

    If you have a native British Dark slate (like Welsh) then it could be rubbed to this honed finish – I am assuming that you have a very flat smooth finish, and not a naturally, riven or cleft finish).

    What I cannot say is if it is already ‘polished’ to it’s limit or not. If not, then you would need to use diamond hand pads (finer grades) or hire a small grinding machine and use diamond or silica carbide pads on that. This is not easy to do in-situ without the right equipment, it needs to be done wet also.

    If you cannot do this, or if the slate is already finished to the highest sheen possible for that stone, then all you can do is add chemical polish (like wax) and buff that to a shine. However, this should be done after the application of a sealer, and that sealer should be an impregnating type. One possible pitfall is that a good sealer is going to want to repel the wax so it might be tough, at least initially, to get the wax to adhere (you may have to wait until the hearth has been cleaned a number of times, and the initial surface effects of the sealer have lessened)

    Hope this helps

  50. Hi there

    Our house needs a bit of a spruce up and I was wondering if there is anyway to remove the gloss paint (that is now peeling) from the decorative slate that is clad onto the bay section between the two bay windows. Its is quite a big area 4m by 1.5m so the less labour intensive the better to be honest. Its a 1930s semi and I’d quite like to restore certain features or imitate the orignal effect. Alternatively (I’m pretty sure you’ll hate this option, but here goes) is there a paint that would make it look more like slate again?
    Whilst Im asking there are also decorative green tiles on the exterior, would you have any idea what to use to clean these up, I have already scrapped a bit of te paint off but its the edges of the tiles that the paint really has a hold on. I appreciate this isnt strictly slate or stone but I thinking you may know as well.
    By the way, thanks for sharing your knowledge, its very god of you, the internet is a wonderful thing!
    Kind regards

    Carol Weston

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