Limestone is one of the most popular natural stone for construction. It has been the choice of many since ancient times. Limestone can give any room or patio a classic, historic feel.
A common stain on Limestone are black spots, which are commonly known as black algae, which is actually not an algae but a bacteria which feeds on moisture and calcium carbonate – the principal material of limestone. It can be caused by heavy exposure to water – like rain. The best way to clean off black algae is to scrub it with a mixture of oxidized bleach and water. Applying penetrating sealant to the limestone surface may protect the stone from further infection from black algae. Constant maintenance is needed if Limestone is located outdoors to preserve its classic beauty.
If black stains cannot be removed by bleaching, it maybe is time to call a professional stone cleaner/restorer.
























