Celebrex arthritis drug safety study surprises heart experts. Back in 2004, a popular arthritis drug called Vioxx was pulled off the market when studies showed daily long-term use could increase the risk of heart attack, stroke and death.
How Steel is Made: a Brief Summary of a Blast Furnace: There are two types of metals, ferrous & non-ferrous. Ferrous comes from, or contains iron, while Non-Ferrous does not contain iron. Some examples of ferrous metals would be mild steel, cast iron, high strength steel, and tool steels. Examples of non-ferrous metals would be copper, aluminum, magnesium, titanium, etc. To make steel, iron ore is first mined from the ground. It is then smelted in blast furnaces where the impurities are removed and carbon is added.
As was stated in other answers, they are both naturally occurring and man-made. Many elements are technically a metal but none occur in nature in ready-to-use condition. The most common metal, steel, is an alloy consisting mostly of Iron and Carbon. The iron is reduced from iron ore which was mined from the ground.