Improving upon nature

Not all iron may be used for the purpose of making fences. Iron is a natural element that is extracted in the form of ore from the earth's crust. It is ductile and malleable, but is not very strong. If, however, there is some percentage of carbon present in it, it can be made stronger.

Cast Iron

Iron, with all the impurities present in it, is called pig iron or cast-iron. It contains traces of manganese, silicon, sulphur and phosphorus. It is stronger than pure iron and is one of the less expensive forms of the metal. When a molten form of this iron is poured into casts, it is called cast iron, and these specifically shaped pieces of the metal may be used for whatever purpose they are designed.

Worked Iron

Wrought iron, on the other hand, is essentially iron, with no impurities, not poured into casts but hammered and 'worked into the desired shape'. It has great tensile and compressive strength and replaced cast iron as the preferred medium for furniture and outdoor fixtures in eighteenth and nineteenth century Europe.

Steel

The other commercially popular form of iron is steel. An alloy of pure iron and carbon, it can further be categorized into mild and strong steel, depending on the percentage of carbon it contains. Steel is very strong, but lacks aesthetic appeal, at least for furniture and adornments. Moreover protracted exposure to the elements does cause a layer of ferric oxide or rust to appear, hence it is not the best choice for any outdoor adornment.

Steel vs. Wrought Iron

However, because it could be mass-produced, mild steel had almost eaten up the market for wrought iron in the twentieth century. This century sees a revival of wrought iron. Because steel corrodes and stains the paint. Also, electric welding, which is how mild steel is welded, does not endure as well as welding by fire.

Powder-coated steel

Of late, powder coated-steel has made its appearance in the marketed. To the untrained eye, it is steel that looks black, like iron. But there is more to it than meets the eye. The sprayed molten metal coating has added tremendously to its durability and to its aesthetic appeal. Both steel, and its powder-coated version, are obtained through a number of expensive processes and are consequently, on the higher side.

It is clear then, cast iron and wrought iron are the only ones that recommend themselves as adornments for the great outdoors on account of their durability or cost or both. Earlier, cast iron was the popular option, owing to the reproducibility of thing from a cast, whereas each item of wrought item used to be crafted by hand. But the advent of the mechanical age changed all this. Better textured wrought iron has appeared since better machines came into being. On the other hand, cast iron has improved, from strength to strength, and hence they remain competitors for the ornamentation of the outdoors.