One of the reasons that you won’t find a dedicated ‘slate seaerl’ is that most stones can be treated with similar cleaners and slate is usually pretty resillient stuff.

Look for a general mild, neutral cleaner that says it is ok for tiles and stone for regular cleaning.

Apart from that, use a mild to medium alkaline cleaner like Xtreme Clean by All For Stonefor deeper cleaning.

Try to avoid acid based cleaners.

The dullness you report may be a reulst of the original sealer wearing down -this is normal for coating sealers, or it could be a build up of detergent, leaving a patina, normally fixed by giving the floor a good deep clean with an alkaline cleaner then rinsing well with water and even rubbing it dry with towels.

If you had a coating sealer (one that was on top of the slate, that maybe had a sloght sheen to it) and this has worn (through alkaline cleaners and/or wear from foot traffic) then this would account for the dulling and the makrs (as the sealer has gone, so to has the stain protetction) – a good deep clean as detailed above then reseal should fix it. From then on try to use neutral or mild cleaners rethat than alkaline for every day use.

If it was an impregnating sealer then again it may have diminished a bit so again, deep clean and top up the sealer when done.

Hope this helps, if you have further questions please feel free to ask, if cou could tel more about the sealer used that may help

Ian

Two possible reasons, one is somewhat more obvious to spot, and that is simply somthing above the slate that is rusty, like a metal bucket, maybe a haning basket made of metal that has water drippig from it, some other fixture or fitting that is rusting and is either in contact with the floor itself, or has water coming fro it that is.

The other and perhaps more common situation is that minerals within the slate itself are oxidising. Slate is made up of many original components like clay, and these can contain minerals, and sources of iron in one form or another. When the slate is first cut and finished into tiles, a new, fresh split face is exposed. Up to this point that part of the slate was ‘inside’ the stone, not exposed to oxygen and moisture

Now the slate face has been exposed to both, and any hitherto invisible iron-bearing mineral, has been allowed to react with water and air, the moisture can come from above – cleaning and washing, or from below (rising moisture, most slates are pretty impervious so moisture travelling up through them from below is less likely), or from installation, there is a lot of water in grout, and maybe moisture from the sealant?

So any number of reason but, often slates like this will simply react with the ambient moisture within the air over time, and so this I think is the most likely explanation – the iron-bearing minerals, now exposed, have over a small period of time begon to oxidise or rust -hence the colour and rough feeling.

Much of this will rub off, and you could reduce it with a little dilute phosphoric acid cleaner – but it may come back over time, however each time you clean it it may reduce in intensity and take longer t come back. You may or may not eradicate it completely. It is however a natural occurance with this type of stone, just like sap coming out of pine, or wood fading or yellowing over time.

Hope this helps
Ian

can you recommend a slate cleaner brand? I can’t seem to find any floor cleaner that expicitly says is suitable for slate and have ran out of the cleaner we were given when the floor was laid.

We have slate flooring in our entrance hall, utility and kitchen as we were advised by our builder that it was extremely durable.

I’ve unfortunately found it quite difficult to keep clean (even though it was sealed twice) and it doesn’t seem to matter how much I clean, but the floor still looks dull with persistent marks. Do you have any advise on how to tackle this?

Many thanks,

Dawn