Given all the contention currently to do with 'plastic' none of it really sticks to the material that in so many ways it emulates. A horn is a permanent pointed projection on the head of various animals consisting of a covering of ’hard hair like material’ keratin – https://en.wikipedia.org/wiki/Keratin – and other proteins surrounding a core of live bone. Horns are distinct to antlers which are not permanent. In mammals, true horns are found mainly among the ruminant – https://en.wikipedia.org/wiki/Ruminant
As a substance is harder and heavier than wood, but lighter and more elastic than bone. Horn has a tear length of about 31 km. Its compressive strength is up to 30 kN (3 tons) per square meter. It is under pressure up to 3% elastic. That is it is reversibly compressible. Horn is more resistant to pressure than on pull, it is overstrained by bending, so it breaks on the pull side. It is not combustible, insoluble in water and weak alkalis / acids, but in strong alkalis / acids. The pigment-free horn can be transparent animals, human fingernails.
Prior to the invention of the plastics, horn was the substance that was often used like platic is currently. Today it is mainly used for the manufacture of buttons, combs, spoons, knives and jewellery such as carvings, although it has often been imitated and almost replaced by cheaper plastic. However, due to its properties – elasticity, compressive strength, resistance to environmental influences etc. – it is a material of higher quality than plastic. In the case of combs, for example, the press seams, which are present in plastic and which can damage the keratin of the hair, are missing. It is also suitable as a material for sheets because of its reversible deformability.
Then there is also the Shofar of Horn, which is blown at the worship on the Jewish New Year's Day Rosh ha- Shana and the Feast of Reconciliation Yom Kippur. Likewise the horn goes back to the cattle horns of early days.
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