Shell Homage: bioplastic made from eggshells and nutshells

Egg- and nutshells are a common waste product. Of course, if you have the patience, you eggshells for inlay, but most people will throw them away. With her project Shell Homage, designer Rania Elkalla created a bioplastic made with these shells without toxic chemicals. With this plastic, she made decorative hangers called Pebbles, which contain secret storage places.

There is more to egg- and nutshells than meets the eye. They are underrated because they are perceived as food waste, but you actually make a lot more from them. They are a wonderful natural resource.

What nut- and eggshells have in common is that they are both strong, to protect their content. Eggshells contain about 95% of calcium carbonate, one of nature’s most absorbent materials. They also contain collagen and can capture up to 78 per cent of carbon dioxide in the air. One medium sized eggshell makes about one teaspoon of powder.

Nutshells are ecological natural materials that have different gradients of brown colours, and varying textures. Each nut type has its own special shell properties.

For Shell Homage, all shells were collected from different sources as bakeries, nut shops, university kitchens and other sources. They were then washed, cleaned, dried in the sun for several days or in special ovens, and pulverised.

The egg- and nutshells, as well as cacao shells, in the bioplastic are bonded with organic and biodegradable polymers. Thanks to the shells, the polymers become stronger. The mixture is put through production techniques such as extrusion, pressing and injection moulding. The material, which is 100 per cent biodegradable, can be drilled, sanded, or laser cut. The plastic is coloured using food pigments. Each batch is different, depending on how homogeneous it is mixed, how much colouring is added, and how much shells are added to the polymer.

The Pebble hangers contain storage compartments on the side. They are designed to store small items that easily get lost, such as keys and USB sticks.

Elkalla is designes 3D products, illustrations, patterns, experimenting with materials, branding and integrate between different design groups. You can contact her via

The Shell Homage project won the Italian A’ Design Award 2016 in the category Furniture Accessories, Hardware and Materials Design.

Photos: A’ Design Award 2016