Calcium Carbonate Geopolymerizing
Erco Lai
Graduate 2021, Master Industrial Design

What did you find out with this research?
Geo-processes such as mineral formation can be the basis of new manufacturing methods.

What is the technique you based your material research on?
First electrolysis then an adapted version of geopolymerization. I consulted an earth scientist and a scientific research institute. I mainly worked in the Industrial Design department studio. We built a small workshop ourselves with leftover materials from previous students and some second-hand machines. There, I smashed seashells with hammers/metal beams into chips, then used a coffee bean grinder to make fine powder.

Materials:
Calcium carbonate (You can source seashells from the beach at Scheveningen. Or use lime pellets, extracted from the water-softening process), waterglass. You can experiment with other minerals like bentonite, slag or lava sand.

Workshops:
KABK Hack Lab
KABK 3D Lab

KABK Metal

Steps:
1. In brief, the process is like making concrete. Pretreat the ingredients. For seashells, you can sort them in different colors then grind them into powder; for limestone, find fine powder when you are in the quarry; for lime pellets, sieve them into buckets and use different sizes with different proportions.

2. Mix dry ingredients with waterglass or lye. You can also add bentonite into the mixture to increase plasticity.

3. Wait for mixture to solidify. It can be put into molds or sand casts. In general, it takes 1-2 days to finalize the reaction, although this will vary with room temperature and the proportion of waterglass used.

Health and Safety Precautions:

Waterglass and lye are strong alkalines so do not touch them with bare hands. When mixing the ingredients use gloves, and avoid using aluminum containers for storing lye.

This recipe is part of Touching: A Research Method in Art and Design, an exhibition curated by architect and KABK tutor Laura van Santen, featuring the materials and research of students, tutors and workshop instructors from the KABK.

More information on the display, all samples and recipes can be found here.