All types of limestone sealer fall under the 2 following categories
Topical Sealer (film forming, coating or surface sealant)1-3 year lifespan
Topical Sealers are products which simply sit on the top of the limestone substrate, acting as a barrier between the stone itself and any potential blemish. They are applied to the surface and once cured, harden to form a visible film. In general, these are not always suitable for use with materials such as limestone as they do not allow the stone to breathe and can become dangerously slippery, particularly when wet.
- Can tend to abrade easily, leading to obvious areas of scuffing or wear
- Will need to be re-applied quite regularly
- Can build-up over time to impart a varnish-like appearance
- Lower quality coatings tend to turn yellow when exposed to UV light (sunlight)
- Trap moisture in the substrate itself, leading to problems with efflorescence or damage
- Longer lifetime as the protection is contained within the substrate, and not simply on the surface
- Not affected by UV light
- Allows the stone to 'breathe', retained moisture can escape
- Surface does not become slippery

Impregnating penetrating sealants actually penetrate into the limestone substrate itself, soaking into the microscopic pin-holes and open fissures which make up its natural texture. A clear impregnating sealer won't change the look or feel of your sealed limestone, won't affect the stone's ability to release vapour and will last much longer than film forming sealers.
Limestone will vary in hardness and is always porous – if you apply a small amount of water to an unsealed limestone surface it will be absorbed in seconds. The porosity of limestone is also affected by the finish – for example a highly polished limestone is less porous in comparison to limestone with a honed (matte) finish.
Fluoro-chemical technology integrated into Australian GOLD is the most advanced technology available, providing the ultimate long term protection against water and oil-base stains. The micro-molecular formula chemically reacts with the stone surface to create a bond that is stronger than any other conventional sealer.
A deep penetrating sealer won't affect the slip resistance of your surfaces

is a premium penetrating sealer that you can use both for interior and exterior limestone tiles. This product penetrates deep in the stone, creating an invisible barrier against water and oil based stains. At the same time, it allows any built up vapour to escape. is well known because of its special molecular structure, which makes this sealer more resistant than other products.