Wrought Iron
Wrought iron is one of the most common metals used for making outdoor furniture and has been used for literally thousands of years for other purposes as well. Wrought iron literally means “worked” iron and that name does well to describe the processes by which it is made. This type of iron is the product of pure iron ore that is incompletely melted and then pounded, bent, twisted, and folded—in other words, worked.

Because of wrought iron’s properties of durability combined with its malleability and ease of welding, it has long been popular for furniture, handrails, and other ornamental uses. If you desire a classic, timeless look for your outdoor furniture, wrought iron is a great choice. The elegant curves and antique look gives a classic, Victorian feel to the furniture.

The main drawbacks to wrought iron are its weight, its susceptibility to rust, and its hardness. Iron is quite heavy and wrought iron furniture can be quite cumbersome to move about when needed. For older individuals and for those lacking the ability to easily move heavy objects, wrought iron may not be the best choice.

Also, if not properly treated with a waterproofing agent, the furniture can corrode and rust due to the elements. The other option to avoid rust is simply to move the furniture indoors to a garage or cover it when not in use. However, due to its aforementioned heft, moving it can prove to be quite a challenge for some people.

Finally, wrought iron is obviously quite hard and uncomfortable to sit on directly. Therefore, it is important to make sure that your wrought iron furniture also comes with cushions to place on the seat for comfort. This usually isn’t an issue as most furniture makers are fully aware of this drawback and offer cushioning anyway. However, if you are having your furniture custom made, it is important to make sure you get the cushions as well.

Aluminum
Aluminum is often a more popular choice than wrought iron for patio furniture because of the resistance to corrosion and lighter weight. Indeed, aluminum is among the most important metals in the world due largely to these very properties. Actually, at one point in history aluminum was considered even more valuable than gold and Napoleon had his table set with aluminum plates when important guests arrived!

The property of aluminum that makes it so valuable for outdoor uses is its resistant to rust due to the thin layer of oxidation that forms when exposed to air. The dull, silvery appearance that is the hallmark of aluminum is actually the product of this oxidation. Thus, it makes sense that this material would be so popular for outdoor use in furniture as well as myriad other applications.

Because of the benefits of aluminum over wrought iron, you will find that sets of aluminum furniture will usually cost a bit more than a similar wrought iron set. However, many find that the benefits to using aluminum over wrought iron outweigh the detraction of the increased cost. It is far easier to handle the furniture because of its light weight and it can stand up to the elements because of its corrosion resistance.

Many furniture makers actually make furniture using “cast aluminum.” Like the name implies, this type of aluminum furniture is made by pouring molten aluminum into a cast which is made by pressing a wooden mold into sand. Once the wooden mold is removed from the sand, the impression left is where the aluminum is poured. Once the aluminum hardens, the sand is simply knocked away leaving a beautiful aluminum cast. This technique also allows fine detailing.

By using this technique, aluminum chairs can be made far more comfortable than wrought iron chairs and can be used by themselves—no cushions needed. Because of these benefits, cast aluminum has become far more popular than wrought iron and is used almost exclusively for metal outdoor furniture.