This was used when the price of copper went up.

Only around the year 2000 did researchers find that these patients have very low levels of copper in the blood.

The use of copper in these plants is described here.

Individual pieces of copper were sometimes given names based on their value.

Looking down, he saw a roll of copper in it.

The story is told that a friend was talking to another about a certain type of copper found in England.

By May 1992, however, the price of copper had declined to about its 1980 level.

The box was of copper, and therefore would have been easily seen.

She could distinguish the sound of copper as money changed hands.

The cultural role of copper has been important, particularly in currency.