In 1854, aluminum was worth $272 a pound -- $15 more than gold.

The malleable metal’s value had dropped $159 a pound by the next year and could be bought in 1897 for 36 cents.

Today, aluminum is worth 77 cents a pound.

Worth, of course is a relative term. The raw material may have a certain value, but what is a material worth that is found probably in every room of the house, including the garage?

Aluminum is truly priceless.

The Carnegie Museum of Art, Pittsburgh, surveys aluminum’s history and functions in the show "Aluminum by Design" through Feb. 11.

Alumina, an extract of bauxite, is abundantly found in clay and early 19th century chemists looked for ways to isolate it and try to discern its properties.

Danish chemist Hans Christian Oersted did it in 1825, and Friedrich Wohler of Germany slightly perfected the process two years later. But a test tube with a couple of aluminum globules Wohler produced in 1854 showed the journey to making usable aluminum was long and slow.

"For most of the century, it was an uncommon and expensive metal, made by a handful of persistent experimenters and entrepreneurs (none of whom would ever get rich on aluminum), and more likely to be encountered in a jeweler’s window or a science exhibition than an everyday setting," Robert Friedel, professor of history at the University of Maryland, wrote in the show’s catalog.

Aluminum -- which is made by passing electricity through alumina that has been dissolved in molten cryolite -- had its champions even when it was rare and difficult to produce. Napoleon III promoted it for commercial and military use.

Some of the most important items in the show, as identified by organizer Sarah Nichols, are a baby rattle commissioned by Napoleon to commemorate the birth of a son in 1856, and a kitschy centerpiece of playing children given to the emperor in 1858 by Charles Christofle to thank him for royal patronage.

An eagle flagpole top from 1860 shows how the metal was initially used, to replace others. The aluminum eagle was lighter than the bronze ones France had made.

"If you carried this into battle it was lighter and you could carry it that much faster," Ms. Nichols explained.

The key properties of aluminum, such as corrosion resistance, ease of casting, light weight, malleability, conducts heat and electricity, nonmagnetic and recyclable, were becoming known, but generally people still hadn’t figured out what to do with it.

"It takes some time for a material to establish itself, for it to develop its own rhetoric," Ms. Nichols said.

Aluminum developed its own rhetoric in the 20th century.

Although the seeds of the transportation revolution were planted in the 19th century, it was in the 20th that cars, air travel and other advances profoundly changed lifestyles. Aluminum was there from the beginning, in cars, motorcycles, airplanes and airships, all of which are represented in the show.

"If there was one thing aluminum was destined to revolutionize in the 20th century, that was transportation," said Ms. Nichols.

The properties of aluminum gave designers the opportunity to keep up with Modernist ideals, such as futurism.

"Aluminum lent itself to streamlining," Ms. Nichols said. "It was malleable and you could create these complex curves."

Once the transportation industry proved aluminum was a material of the future, others looked to make it part of established and burgeoning industries.

George Steadman contacted aircraft manufacturers about how they used aluminum in developing garden furniture in the 1930s.

Aluminum looks similar to silver, making it an able replacement for the more expensive metal in silverware and kitchen utensils.

"In the 1920 and 1930s, aluminum was escaping from the kitchen and into the rest of the house," Ms. Nichols said.

At about this time, a small, former mining company in Brockway, Pa. -- Wendell August Forge -- was making ornamental ironwork when Alcoa decided to build a new research facility in New Kensington.

Alcoa planned to have the entrance gates made of cast aluminum, which was in line with its goal of making the building a structural and artistic testament to aluminum.

Wendell August approached Alcoa about trying to forge the gates, which many thought was not possible.

"It took a long time to learn to forge aluminum," Ms. Nichols said. "Because it’s a different material from iron you can’t forge it the same way."

The forge had never worked with aluminum before, but created a process for making hand-wrought aluminum that changed the company’s course.

Impressed by the forge’s work for Alcoa, Edgar Kaufmann asked the forge to make items for him to sell in his stores. "Wendell August Forge never looked back," Ms. Nichols said.

The company moved to Grove City in 1932.

The gates are in the show, along with a 1930s desk set that is one of the first giftware items the forge produced.

Former employees of Wendell August Forge also made their marks in the growing decorative aluminum industry. The work of Arthur Armour and James DePonceau, both of whom died in recent years, is included in the main show and a complementary exhibition on collectors, who are dubbed "alumi-nuts."

The future of aluminum seems as wide open as any time in the 20th century. It’s a good material for robotics. Car companies are looking for ways to incorporate more aluminum. Even the fashion industry has flirted with it.

"Some of the applications were not as successful as others," Ms. Nichols said. "People would think of things and aluminum was not up to it. The engineering and metallurgical world would work on it and the technology would catch up. Certainly, now more than ever, people are working to make sure there are no boundaries."

But there are signs that aluminum has a shelf life. Just as aluminum eliminated wood from tennis rackets, aluminum has become old-fashioned on the court, ousted by graphite and titanium. Aluminum siding is becoming passé, thanks to vinyl.

The show will be up through Feb. 11. Information: (412) 622-3131.