Philippine Metals Inc.
InvestorsInvestment Highlights
Show printable version of 'About Copper' item in a New Window
Copper, or Cu, is a soft, malleable metal with a very high thermal and electrical conductivity. In fact, copper has the second highest electrical conductivity of any element after silver. It's often seen in an oxidized state in which it gives of a blue or green patina.

As consumption in countries such as India ad China increases, copper supplies are becoming scarcer. China alone accounts for approximately 22% of the world copper demand. The price of copper has quintupled from the 60-year low of US $0.60 per pound in June of 1999. As of November 2009, the price of copper was over $3.00 per pound.

Uses of Copper

Copper has been in use for at least 10,000 in a wide variety of applications, often as an alloy due to how soft the metal itself is. These applications include:

  • Piping

  • Electrical wiring

  • Electromagnets

  • Circuit boards & other electronics

  • Lead free solder

  • Vacuum tubes

  • Roofing

  • Ship building

  • Lightening rods

  • Door knobs

  • Cookware

  • In hospitals as bacteria won't grow on its surface

Copper Mineralization
Porphyry copper deposits are currently the largest source of copper ore and a type of deposit that is common to the Philippines. Almost all mines exploiting large porphyry deposits produce from open pit mines.

Porphyry deposits are formed by igneous activity (volcanic) and tend to be large but low-grade deposits. The mineralization typically forms veins or breccias bodies in the intrusion itself or in the surrounding rock. The fractures are often radial, extending like the spokes on a wheel, or concentric with the intrusion at the centre.

The rocks around the deposit are highly altered since large volumes of hydrothermal fluids have circulated through them. In the rocks farthest away from the intrusion, many of the primary minerals are leached. In rocks closer to the intrusion, the primary minerals are completely destroyed and replaced by micas and clays. At the centre of the hydrothermal system, where it is the hottest, hydrothermal feldspars are formed.

Another process, particularly important to copper porphyries, is called supergene enrichment and occurs after the primary copper deposit has formed. Weather processes leach copper out of the upper parts of the deposit; the copper-bearing solution travels downward though fractures and pore spaces until it meets the water table. Because the copper is no longer in contact with the air, it becomes unstable. It precipitates, forming copper-rich minerals such as bornite, chalcocite and cuprite. This enriched zone can have substantially higher ore grades than the primary mineralization.