3. Fes una ressenya històrica del ferro.
Iron is probably the most precious of all metals. It has been used since
prehistoric times. The name “iron” comes from the Scandinavian “iarn”. There
are some stories about the origin of iron. Some say that it was a gift of the
Gods. Others that it came from meteoric sources. Iron can be reduced from
several ores in the Nature. It's told that iron was produced for the first time
when some ore pieces reduced when fires were kept for a long time, and people
observed that with higher temperatures iron lead better. This method was
improved until the creation of furnace.
Iron was known more than 7000 years ago, and in China
they used the steal since 2250 a.C. In the Prehistoric, Bronze was more used than iron, because it was
easier to manipulate. But it was abandoned by 500 a.C. because of the lack of
copper and the abundance of iron. This fact leads people to develop new
techniques for iron working.
After the fall off the Roman Empire, the iron
production suffered an important development. In particular in Spain with the
famous steel blades of Toledo and its craftsmen, who went to other countries
where they introduced the bloomery, which originated the big furnaces. The products
got obtained from the bloomery were a kind of malleable iron or steel. The
furnaces produced a variety of iron that was suitable for casting and molding.
When the Cort discovered a transformation process to forge this kind of iron,
with lower costs, the production considerably increased in England.