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Bronze and Brass

About 6,000 years ago people discovered that copper could be made harder if mixed with tin. This alloy is called bronze. It was so widely used for many years that this period of time became known as the Bronze Age.

If you had been a soldier in Ancient Greece you would have had to stop in battle to straighten your bronze sword. But bronze was a great improvement on copper, which bends even more easily. Most pure metals are weak and soft. But two soft metals mixed together make a harder metal called an alloy. Bronze is an alloy of copper and tin. It was the first alloy.

Tin was the fifth metal discovered by man. It is a soft whitish substance. Various proportions of the two metals produced different qualities in the bronze. Most early metal-workers used about eight parts of copper to one of tin. Because weapons made of bronze were harder and stronger than those of copper, tin became very important. However, there was little tin to be found in western Asia - still the centre of the metal-working world. Mostly it was found in Europe, and the merchants of Troy, who brought their goods to Europe, began loading their boats with tin on their return journeys. In England, tin was discovered and mined in Cornwall and was a main export for a long time.

When zinc was discovered it was used to produce an important alloy in combination with copper. This alloy was brass, a hard-wearing, yellow metal which was valued more than bronze. The exact date of discovery is uncertain but it was probably about 200 BC. Brass is often mentioned in the Old Testament, most of which was written before zinc was discovered and therefore when there could not have been any brass. The bibical metal must have been either bronze or copper, and the word 'brass' is the result of a translator's error at some time. So, bronze and brass were the first alloys - man-made metals.

 



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