Limescale in the Neo-stone Age

Limescale in the Neo-stone Age

Calcium carbonate is one of the most common materials on Earth. It can be found dissolved in rivers and lakes. We can also find it in skeletons and shells, and see it form stalactites. But one place we often see it is in our water systems. Limescale is seen as a nuisance waste matter that is produced in our water softening processes. Erco Lai’s research attempts to reintroduce limescale as a promising material, with a focus on creating “geopolymers”, using a chemical process to bind inorganic materials together.


Limescale is a hard chalky deposit that often builds up inside kettles, hot water boilers, and pipework. Erco Lai explores the possibilities of making it as a building material. He is interested in how minerals can be applied to design, and his research begins by looking at mineral formation as a starting point for harvesting from geo-processes. Mimicking geo-systems in order to rethink manufacturing systems. While studying geomorphology, he studied the natural processes such as dripping caused by gravity, decomposing by rain, evaporating by the sun, and shaping by the wind. While the processes and materials he focused on were minerals, petrification, crystallisation to accretion are the promising processes.


The limescale in our homes and water systems is difficult to collect, as only a small amount is produced over time. Due to this Lai went to water purification centres, where he discovered the by-product, mineral pellets, from the water softening process. He uses a geopolymerization process which polymerises silica and alumina containing minerals using alkali solvents. Cements are the most common application of geopolymerization, which give a strong final material. For one of his first projects Lai powdered seashells and dissolved them with vinegar. This solution was then put into Petri dishes for 3-5 days to study the crystallisation of mainly calcium. From there he began to experiment with limescale and limestone. He followed a similar surface process, as well as dissolution on some objects, such as metalwares. During this experimentation it was also tested to see if minerals can be adhesive, and act as joinery.




Erco Lai