Acid stained concrete can bring a warm unique look to concrete slabs. The mottling that occurs via the chemical reaction with the minerals in the concrete will never be duplicated from slab to slab. Therefore you will always have a unique floor.
Not all concrete is a candidate for an acid stain. If your concrete has had a previous finish such as stain, tile, carpet it may not be the best solution to beautify your slab. The reason lies deep in the pores of the concrete. A professional decorative concrete contractor will understand this and explain to you your options. Such as a polymer modified cementitious overlay. With a coating such as this, you now have a blank canvas which your contractor can create his work of art. We can’t stress enough to do your research on your contractor. For example, in the picture below, you can see that we created several samples for the client in his home on his slab.
If it weren’t for tests like these, we would never know the final outcome of the stain that is going over original concrete. There is no way to predict it. In addition, these tests showed us something that could have presented a big problem down the road. And that is the presence of an over abundance of cure and seal that they used when the slab was poured. This will hinder the stain from penetrating, the sealer from adhering and there is now way to tell without tests. We originally used a swing buffer and sanding disk for the first round of test. When we were able to scratch off the acid stain with our nail, we knew this floor had to be be prepped via mechanically grinding.