staining on blue stone

I just had a lovely blue stone patio, 2 in fact, installed. My contractor used a product called "gator dust" instead of grout/cement....whatever the more traditional material would be to put between the stones. Almost as soon as it was put in, the edges of many of the stones darkened, in some cases a rust color appeared on the edges. In some cases no discoloring appeared. They give the appearance of being stained. It is most unattractive and I'm wondering if you can give me any advice as to what products/solutions would be best to try to remove the staining or, am I stuck living with it as it is (I hope not. I have seen your advice for how to deal with efflorescence and thought that might be worth a try.) Thank you in advance for any advice you may be able to give me.

Comments for staining on blue stone

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Gator dust staining
by: Bob

Have had similar bluestone staining from gator dust. I like the gator dust product and feel my contractor was sound in his work practices.

I used a very high grade bluestone for my patio - no iron veins and a beautiful even bluestone appearance throughout.

After the gator dust installation I had:

1. Excess gator dust caked to the bluestone. Most of this has been removed by the contractor pressure washing.

2. A few areas of rust stains from the old galvenized gutters which I've had since replaced. I've trired lime cleaners but they don't appear to be effective. Most of theses stains (are on the gator dust joints, not the bluestone).

3. Dark, olive blue green mildew looking stains at random spots on the patio. I just tried a 50-50 bleach solution which doesn't seem to have an effect.

My next pursuits will be acid and more pressure washing. Once I achieve the original bluestone look I'll definitely seal the patio.

Cleaning Gator Dust haze.
by: Anonymous

An insider secret is to use Smart and Final stores toilet bowl cleaner. Used it on my High Desert Flagstone patio after the Gator Dust and all the stains were removed and the natural color shined.

Bio Klean
by: David

Using Bio Klean and/or Sure Klean could be a good solution for you.

You should call Prosoco at 1-800255-4255 and see what they suggest. We've never laid stone in gator dust, so we can't give you any specifics about that.

You should also ask them about 600 Detergent. It could be strong enough to eliminate your rust.

Great luck and when you get it resolved, I'd love to know how you did it, so I can spread the word to others. Just shoot me a quick comment back!

Take care,


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