A Catechism of Familiar Things; / Their History, and the Events Which Led to Their Discovery. / With a Short Explanation of Some of the Principal Natural Phenomena. For the Use of Schools and Families. Enlarged and Revised Edition.

by Anonymous

Opacity, want of transparency or clearness.

What are Metals called in their natural state?

Ores; so named because the metal contained in them is either mixed with other metals, or with mineral earths, from which they are separated and purified by various means: such as washing, roasting, &c., but the method is always regulated by the nature of the ore.

What is Copper?

A hard, heavy, ductile metal, found native, and in many ores; of these the most important is copper pyrites, which is a sulphuret of copper. Next to gold, silver, and platinum, copper is the most malleable and ductile of metals; it may be drawn into wires as fine as hair, or beaten into leaves as thin as those of silver. The rust of copper is very poisonous. Copper, mixed with a certain quantity of tin, forms bell-metal. With a smaller proportion, it forms bronze, a substance used in sculpture for casting figures and statues. It is an abundant metal, and is found in various parts of the world. Native oxides of copper are found in Cornwall, Siberia, and in North and South America.

Oxide, a substance combined with Oxygen,[8] in a proportion not sufficient to produce acidity.

Sulphuret, a combination of sulphur with a base.

[8] See Chapter XIII., article [Oxygen].

What are the uses of Copper?