ABOUT
US

PRODUCTS

COPPER

COPPER IS DUCTILE

Compared to other metals, copper is very ductile, meaning that it can be drawn through a tiny hole into very fine wire without breaking. Refining improves the ductility of copper so that extremely fine wires can be drawn. Impurities increase the chance that the wire will break during the drawing process.
Copper conducts electricity.

Only silver conducts  electricity better  than copper and  traditionally costs 40  times the price of  copper. Refining improves the conductivity of copper by lowering the electrical resistance. Resistance is like friction to electricity, and it causes energy to be lost as heat in poorly conducting wires. Improved conductivity means more energy is delivered to the desired destination when you flip that switch or turn that dial.

COPPER IS RECYCLABLE

More than one-third of the copper refined in the United States comes from recycled material. That’s a higher recycling rate than aluminum! Scrap copper comes from manufacturers of all sorts of copper and brass products. The copper is melted and cast into anodes and refined just like ‘new’ copper from the mines and smelters.

ASARCO OFFERS REFINED COPPER IN A WIDE
VARIETY OF SHAPES AND SIZES

Amarillo Copper Refinery’s Management/Quality Systems is ISO 9001:2000 certified.
Copper production is monitored and controlled, assuring compliance with the world’s highest production standards. Systems are calibrated, controlled, and documented to
affirm top quality performance and products.

ASARCO: A RELIABLE SOURCE FOR REFINED COPPER

One of the key factors in maintaining a reliable supply of product is
close control over the flow of materials during the production process.
ASARCO maintains this control through its integration of operations and
by applying quality control production standards.

MINES

ASARCO’s Ray Unit has the capacity to produce approximately 100
million pounds per year of electrowon copper cathodes from its
SX/EW plant. The Company’s Silver Bell Unit produces about 40
million pounds of SX/EW cathodes annually.

EXPLORATION

To maintain its reliability as a supplier, ASARCO conducts an
ongoing exploration program for new copper-bearing mineral
deposits and continuously drills at existing deposits to expand
and delineate the ore body.

HOW TO SPECIFY COPPER SHAPES:

ASARCO’s electrolytic copper shapes are
made to conform to the specifications of
the American Society for Testing and
Materials (ASTM). The applicable
permissible variations specified by ASTM
are listed in the tables showing dimensions
and weights for the various refinery shapes.

The high-quality, electrolytic tough pitch (ETP) copper cathode and rod
produced by ASARCO meets or exceeds the chemical analysis specified
by the American Society for Testing and Materials (ASTM).
So, too, does the Company’s ETP copper cake.

+   ROD

CONTINOUS-CAST ROD SPECIFICATIONS

ATR BRAND, ELECTROLYTIC TOUGH
PITCH (ETP) PICKLED AND COATED

Continuously cast copper rod produced at our Amarillo Copper Refinery is
shipped to wire manufacturers all over North America.

Want to know about the process of MAKING COPPER?
Click here to see the video.

MINING

Arizona is nicknamed “The Copper State” because of the great deposits of copper that NATURE has placed here. If Arizona was a country, it would be the second largest producer of copper in the entire world. Only Chile produces more copper than Arizona. The star on the Arizona state flag is copper-colored because the red metal is so important to the state’s economy.

A miner is even depicted on the state seal. ASARCO currently operates three copper mine properties in Arizona:

+ The Ray Complex mine and mill, between Hayden and Superior, Arizona
+ The Silver Bell mine and SX/EW plant, northwest of Tucson, Arizona
+ The Mission Complex mine and mill, south of Tucson

MINING RESOURCES

+ Drilling and Blasting Crew
+ Big Trucks and Big Shovels
+ Truck Dispatch System
+ Dust Control

MILLING

CRUSHING

The haul trucks carry the ore out of the pit along a haulage road with a slope of no more than about nine
percent. They dump the ore into a gyratory crusher which reduces the ore to eight inches or less — about
the size of soccer balls. The primary crusher may send the crushed ore on to a secondary crusher or pile it
directly onto the coarse ore stockpile.

On your tour from the Mineral Discovery Center, you may get to see the haul trucks dumping ore into the
crusher

GRINDING

The ore is ground into a fine powder by large rotating mills. The two types used in the
Mission South Mill are called SAG (semi-autogenous grinding) mills and ball mills.

SAG mills use larger pieces of ore to break up the smaller pieces (autogenous — does it by itself). The
larger pieces break down as well. To help the process along, eight-inch-diameter steel balls are added to
the rocks as they tumble inside the rotating mill (semi-autogenous — gets some help from the steel balls).

When the rocks are about 3/8-inch or smaller, they are fed as a slurry into the two ball mills. These mills
contain literally hundreds of thousands of three-inch diameter steel balls that pulverize the ore until it is
like fine sand or face powder. Only then are the copper minerals broken free of the rest of the rock to be
separated by flotation

CONCENTRATING

The slurry of water and pulverized ore is mixed with milk of lime to raise the pH and small amounts of
special reagents: a frother to make bubbles, and a collector chemical that causes the copper minerals to
stick to those bubbles.

Air is blown into the tank and the mixture is vigorously agitated like a high-speed blender. Rising bubbles
carry the copper minerals up and over the edge of the flotation tank. The bubbles break soon after they flow
over the edge. The copper minerals are then ground up even finer and purified by another flotation process.

The dried copper concentrate of about 28 percent copper is shipped to the smelter. It represents less than
one percent of the material removed from the mine. Concentrate is just a fine powder of the mineral
chalcopyrite which is a naturally occurring compound of copper, iron, and sulfur.

The material that sinks in the first flotation cell goes on to two more flotation cells to recover as much
copper as possible. What doesn’t float is called tailings because it goes out the “tail end” of the flotation circuit.

About 80 percent of the water used in the milling process is reclaimed and re-used. The rest is used
to keep the tailings damp and to prevent wind-blown dust.