A armadura retratada nos filmes é absolutamente desconexa com o que Tolkien realmente escreveu, então você não pode inferir nada deles.
A armadura de doriathrin era na verdade anão, e era correio, não placa, como aprendemos no Silmarillion:
Thingol's armouries were stored with axes and with spears and swords, and tall helms, and long coats of bright mail; for the hauberks of the Dwarves were so fashioned that they rusted not but shone ever as if they were new-burnished.
A armadura dos Noldor também era mail:
And Ulmo declared to Turgon of what kind and stature should be the helm and mail and sword that he left behind.
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But Fingolfin gleamed beneath it as a star; for his mail was overlaid with silver, and his blue shield was set with crystals; and he drew his sword Ringil, that glittered like ice.
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Turgon had opened the leaguer of Gondolin, and was come with an army ten thousand strong, with bright mail and long swords and spears like a forest.
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...the Gondolindrim were strong and clad in mail, and their ranks shone like a river of steel in the sun.
Não há nada sobre a armadura Númenoreana ou da Terceira Era no Silmarillion, mas existe no Senhor dos Anéis, e mais uma vez nós aprendemos que é o correio todo:
Leading the line there came walking a big thick-limbed horse, and on it sat a man of wide shoulders and huge girth, but old and grey-bearded, yet mail-clad and black-helmed and bearing a long heavy spear.
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...the sons of Elrond, that few could tell them apart: dark-haired, grey-eyed, and their faces elven-fair, clad alike in bright mail beneath cloaks of silver-grey.
...
Quanto a se o estilo é original ou emprestado, já que todos na Terra-média usam armaduras de malha, podemos dizer com absoluta certeza que a armadura de todo mundo foi influenciada pelos anões, já que os anões inventaram o correio, como aprendemos no Silmarillion. :Tirelessly he strode from Citadel to Gate, from north to south about the wall; and with him went the Prince of Dol Amroth in his shining mail. For he and his knights still held themselves like lords in whom the race of Númenor ran true.
Their smithcraft indeed the Sindar soon learned of them; yet in the tempering of steel alone of all crafts the Dwarves were never outmatched even by the Noldor, and in the making of mail of linked rings, which was first contrived by the smiths of Belegost, their work had no rival.
Não há mais nada a dizer sobre estilos específicos de armaduras e motivos decorativos, já que isso é algo sobre o qual Tolkien realmente não forneceu detalhes.