planerGO definitions

Material group is used to group materials

clay: aluminium silicate composed of fine-grained hydrated minerals. Its main property is its plasticity when is mixed with water and its hardness after being cooked over 800ºC. It is an essential material in crafts.
metals: chemical element that is a good conductor of both electricity and heat and forms cations and ionic bonds with non-metals.
nature: "Nature" refers to the phenomena of the physical world, and also to life in general.
organic: chemical compounds whose molecules contain carbon joined with other carbon or hydrogen. Usually contains other elements such as oxygen or nitrogen. Natural organic compounds are made by plants or animals and are studied by biochemistry.
plastic: material made by a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass.
sand: is a granular material composed of divided rock and mineral particles. Its texture depends on the diameter of the particle. Its usually found in beaches and it is used also as a component of other construction materials.
stone: in geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids. There are three classic types of stones, metamorphic, igneous and sedimentary.