Loren Florey, age 13, of Chester, PA, for her question:

IS FLINT IMPORTANT TODAY?

In prehistoric times, flint was valued by people because they could chip it into tools and weapons. Today flint has little importance as an industrial product. But it is sometimes used to crush hard substances such as ore.

In the olden days flint was used to make spears, knives and arrowheads.

Later, people learned that they could start fires by striking pieces of flint against some hard metal. But these uses are not needed today.

Flint is a form of silica. It is made from the same material which makes up sand. Most flint is found in the form of fine grained, dark gray lumps mixed with chalk and limestone.

Pure flint is so hard and even grained that it chips in smooth, curved flakes. Geologists classify fint as a type of chert or chalcedony.