Page Index
Introduction
History of Copper
Uses of Copper
Copper Pricing
Copper Geology and Exploration

Introduction

The base metal copper (symbol Cu) is one of the oldest known metals. Copper is softer than iron and is extremely malleable and ductile. It is an excellent conductor of heat and, next to silver, is the best electrical conductor.

Copper also has a low chemical reactivity. Exposure to weather transforms copper's reddish exterior to a blue-green tinge; this film (called "patina") is a mixture of sulfate, carbonate, hydroxide, and oxide, which protects the metal from corrosion.

Because copper was discovered many millennia before any other metal, it had a variety of uses; its primary applications in ancient times were in the fashioning of jewelry and utensils. Today, wires made of copper are a vital component of the ever-expanding telecommunications sector.

Copper ores can be found throughout the world. The chief producers are the United States and Chile. Significant deposits are, however, found in many parts of the world.

For detailed information on copper, visit www.copper.org

History of Copper

Copper's first known usage - as a decorative pendant - dates back to 8700 BC, in present-day Iraq. For nearly 5,000 years, copper was the only known metal, before gold was eventually discovered. It is believed that approximately 7,000 years ago, Native Americans extracted copper in the upper peninsula of Michigan.

Copper got its name from Cyprus, the primary source of copper in the ancient world. In addition to important deposits in Cyprus, copper was common around the Mediterranean - it was found in nuggets on the earth's surface beside streams and on the walls of canyons.

Objects of beaten copper were used by the Chaldeans in the Middle East about 4500 BC, and copper weapons and ornaments of the same period were recovered amongst the ruins of Susa, an ancient civilization located in what is now Iran.

Copper's long history of use in utensils, ornaments, and weapons notwithstanding, the metal did not develop significantly until the late 1800s, when scientists realized the conductive abilities of copper wire. With the introduction of electricity and the development of the telephone system, copper found its greatest use.
The Intergovernmental Council of Copper Exporting Countries (CIPEC) was founded in 1967 to coordinate research and information policies among its members, which include Australia, Chile, Indonesia, the Democratic Republic of the Congo, Zambia, Peru, Papua New Guinea, and the former Yugoslavia. CIPEC is an update of the international copper cartel, a loose, voluntary alliance of major producers that existed from 1935 to 1939.

Uses of Copper

Copper's greatest application today is in the manufacture of electrical apparatus and wire and cables. Approximately half of world output is used to produce a variety of copper wires and cables used in buildings, appliances, computer networks, telecommunications networks, and automobiles. Significant quantities are still used as coinage.

Copper tubing is used in plumbing and, owing to its high heat conductivity, in heat-exchanging mechanisms such as refrigerator and air-conditioner coils.

The metal has a long history of use in utensils and as an artistic medium for sculpture and metalwork. Copper is also used in roofing.

Copper is present in a variety of alloys including brass, bronze, gunmetal, Monel metal, and German silver. Copper compounds are used as fungicides and insecticides; in a powder form, as a pigment in paints; as mordants in dyeing; and in electroplating.

Copper Pricing

Copper is traded on the New York Commodity Exchange, where prices fluctuate based on supply and demand and reports from the leading copper centers. Copper is also traded on the London Metal Exchange; the price is set during two separate sessions each day. First session: 12 noon and 12:30 p.m; second session: 3:30 p.m. and 4:10 p.m.

Copper Geology and Exploration

Copper is by far the most commonly occurring metal and is found in a variety of geological settings. Many of the world's largest mining projects are primarily directed at recovery of copper, often in association with other metals such as molybdenum, gold, and zinc. The principal ore minerals are chalcopyrite, chalcocite, bornite, and native copper.

Worldwide exploration targeted at identifying copper resources began in earnest in the early 1960s and resulted in the discovery of many major deposits; probably the best known are porphyry copper deposits such as OK Tedi and Bougainville Copper in Papua New Guinea. Products from porphyry copper deposits include copper, copper molybdenum, and copper gold. Porphyry copper (molybdenum) deposits generally grade from 0.2 to 1 percent copper and 0.01 to 0.05 percent molybdenum. The copper (gold) porphyries grade from 0.5 to 1 percent copper and 0.005 to 0.3 ounces per ton gold. Exploration for these giant deposits continues in the Americas and in the Pacific "Rim of Fire."

Although few in number, sediment-hosted stratiform copper deposits are also extremely significant producers of copper (plus cobalt, lead, and silver). The Kupferschiefer and Zairian-Zambian copper belts are notable examples of huge copper ore deposits of consistent grade and lateral continuity. Grades of this deposit type are highly variable and range from one to five percent copper and from 0.03 to 0.9 ounces per ton silver. Individual lenses can vary in size from one to over 500 million tons.

Although production from sediment-hosted deposits is dominated by a few large companies and districts, the number of active explorers is equally small. Although both junior and senior mining companies are anxious to re-enter the Congo, political instability has, to date, prevented both exploration and mine development there. Canadian junior Rhonda Mining Corp. and its partner Noranda Mining have been exploring for large, sediment-hosted base metal deposits in the Cornation Gulf region of the NWT. Significant copper grades of 1.5-2.8 percent have been found on surface, while limited drilling has intersected core grading 2.55 percent and 2.4 percent copper.

Volcanic-hosted stratiform copper deposits are also significant producers of copper (plus zinc, lead, and precious metals). The volcanic massive sulfide deposits (labeled VMS in the literature) have been classified into just two major groups: the copper-zinc type and the zinc-lead (minor copper) type. The VMS copper-zinc ores include the Canadian Archean greenstone-hosted ores in the Noranda, Timmins, Chibougamou, Mattagami, Sturgeon Lake, Manitowadge, and other camps; the Japanese Kuroko deposits of the Hokuroku district; the ophiolite-hosted copper ores of Cyprus and the Spanish-Portuguese Pyrite belt deposits. All of these are defined by the presence of submarine volcanic rocks and a massive sulfide (pyrite and pyrrhotite) host. While the grades and sizes of such deposits vary considerably, a typical example would be the Abitibi Belt in Canada, one of the largest Archean greenstone belts in the world. An average grade and tonnage from 52 deposits has been calculated at approximately nine million tons grading 1.7 percent copper, 3.43 percent zinc, 0.07 percent lead, one ounce per ton silver, and 0.02 ounces per ton gold.

A final source of significant copper (plus gold, uranium, and silver) production is the unusual Olympic Dam deposit discovered in South Australia in 1975. This deposit hosts two billion tons of 1.6 percent copper, 0.06 percent uranium, 0.017 ounces/ton gold, and 0.1 ounces per ton silver. The discovery of this deposit, which has been labeled as a type of Proterozoic, sediment-hosted iron-oxide deposit, sparked considerable exploration worldwide. Companies in the mid- to late-1990s are actively exploring the Great Bear Lake district, Canada, for similar copper-rich deposits.