1. What is the best way to clean a gray slate floor? It streaks every time I mop it, and the mop seems to shed on the floor.

Rep: It sounds as though your slate floor has a rough finish, which catches the fibers of the mop as it is dragged across the floor. First, you need to deep clean the floor to remove all dirt and grime. Next, apply a high-quality acrylic sealer. Several coats may be necessary. The acrylic sealer should make future cleaning much easier. Clean the floor with a neutral cleaner and re-apply the sealer as needed. Stonecare suggests using Neugel or Neutral Cleaner.

2. The slate steps on our front porch have developed a hard white deposit coming from the grout lines. How can we clean it off?

Rep: The white deposits are salts, which are bleeding through from the grout joints or from the mortar. An acid wash will be required to remove the salts. If the deposits are heavy, try scraping them off before washing the slate with acid. Several acid products are available for this purpose. The suitable chemical is Deterfug that can remove cement, motar on the suface of stone. Stonecare of Vinastone provides all of dedicated chemicals for natural stone.

3. I have recently laid a black river slate floor. Having grouted the floor with the slurry method, I discovered that the surface of the majority of tiles had grout in the recesses and the cracks. Now the black slate floor has white lines across it. How do you rectify this?

Rep: While I do not normally recommend using acids on any slate surface, this is the one exception. Try washing the floor with a solution of sulfamic acid. You can find this acid at most home centers and tile supply stores. After rinsing the floor with acid, make sure to rinse with plenty of clean water. The best chemical is Disycott.

4. A friend, with the help of a hired laborer, recently completed laying a slate patio on a cement slab. The laborer is recommending a 3% muriatic acid wash before sealing. The supplier of the slate recommends a different bottled product to wash the slate and then neutralizing the acid with another product, all before sealing. What is the correct way to proceed? Is there a particular type of sealer you would recommend?

Rep: You need to be very careful using an acid to wash slate. If you think an acid is needed, use a mild acid such as sulfamic acid. I would not use hydrochloric acid. The only reason to use an acid would be if there is a grout or mortar film on the slate. If there is no film, an acid wash is not needed. In this case, according to Vinastone, simply clean the slate with Neugel or Neutral Cleaner and allow it to dry for at least 24 hours. Apply a sealer designed for use on slate.

5. I am going to put 600 square feet of slate on my new floor. I was wondering if there really is a quality difference in the tile you get for $2.00/square foot at the giant home centers versus the tile you get for $5.00-$7.00 from the local tile store. I don't want to be cheap, but I also don't want to just spend money to spend money.

Rep: Slate is a natural stone product. Depending on where the slate is quarried, you can have major differences in how it will hold up. Examine the slate carefully and make sure it is sound and does not easily flake. Ask where the slate is from and compare it to the more expensive slate. Don't be afraid to ask the salesperson, what is the difference? You might be able to make a decision based on his answer.

6. I am trying to clean an old slate floor. The slate has some type of sealer or wax, which is very dirty and discolored. I have tried many types of cleaners and strippers. I have found one solvent product (xylene), which removes the wax or sealer, but leaves the slate dull. I have two concerns: Will the xylene solvent damage the slate, and how do I restore the shine to the slate?

Rep: The xylene is a solvent that can be dangerous to work with. It will not harm the slate. Stonecare’s suggestion would be to use one of the safe strippers available such as DEC21. To restore the shine, you will need to coat it with Hidrofab AR.