Brian Lee Rupnow, age 13,  for his question:

What is an alloy?

The words alloy and ally both spring from the same ancestor, an older word meaning to bind. In meaning, they are still related. Allies are friends or nations bound together by common ties and interests, An alliance of nations is stronger than the separate nations. An alloy is an alliance between two or more minerals. The minerals are melted together in a furnace and as they cool they bind together to make a new substance. This alloy is able to do a job better than any of the separate minerals.

Bronze is an alloy made from copper and tin,It has a yellow brown color all its own and it is tougher than either copper or tin alone. Brass is an alloy of soft copper and dull zinc.It sparkles with golden luster and is very hard and durable.

We use countless alloys in our everyday world, often without knowing it, Whatt s more, we tend to think that only metals can be used to make alloys. Sometimes non. metals such as silica or carbon are also melted into a seething brew. You may think that an aluminum frying pan is made of plain aluminum. Chances are, it is an alloy. Pure aluminum would tend to melt over a hot flame. The alloy might be aluminum, copper and silicon, which is tougher and has a higher melting point than the pure metal.

There are usually several ingredients in an alloy. Though there are thousands of alloys, they are made from only about 40 different substances. The process of making each alloy is often one tricky step after another. The recipe calls for melting the ingredients together, often at terrifically high temperatures, and then cooling the mixture in just the right way,

Each ingredient is made from tiny building blocks, all fitted neatly together to form a solid mass, These little building blocks are different shapes in each ingredient. The heat separates the solid ;pass of blocks into a runny liquid, In the molten stage, the big blocks from one ingredient mix with little blocks from another ingredient. If the seething mixture is properly cooled, big and little blocks fit together in a firm new pattern. A pattern of large and small blocks is stronger and more pliable than a pattern of all large or all small blocks, This is the binding together which gives an alloy its good qualities,

Each alloy has its own special qualities, When iron is smelted with a soft metal called cerium, we get a hard, brittle alloy that shoots off sparks when scratched. This alloy is used to make lighter flints. An alloy of beryllium and copper refuses to shoot sparks under any conditions, Beryllium copper is an alloy used to make rifle parts. A soft alloy of lead and tin melts and runs smoothly when put in a flame. This alloy is used as a solder to mend metals, When its qualities are known, an alloy is given a special job to do.