An elb from the world of Lord of the Rings was such a good smith that he alone caused a whole war

An important elb from the texts of J.R.R. Tolkien has done some great deeds as a blacksmith. He forged three mighty gems, which led to a war in Middle-earth – long before the action of the films. Which elb is it about? The talk is of Feanor. The elb also bears the title "High King of the Noldor" because he led the eponymous clan of the Elbe. Feanor lived before the events from Lord of the Rings and was the uncle of Galadriel. He was from Valinor…