I started my undergraduate career set on getting a business degree from a local college and working as a branch manager somewhere. Then, I changed paths and decided I wanted to enter medical school and become a doctor. Like most 18-year-olds, I had no idea what I really wanted. As I started taking more science courses, I soon realized I had discovered my calling.
One appealing aspect of science and engineering was how seemingly mundane occurrences could be explained by scientific concepts that apply to a wide range of phenomena. I could wonder about the tiniest details of everyday life and try to use my knowledge of physics to explain how stuff works. I learned a lot this way and enjoyed testing my physical intuition. I’ve gathered a few of my favorite mundane events that are explained by seemingly-esoteric (but ultimately intuitive) scientific concepts.
The two for this week aren’t necessarily scientific concepts that explain mundane topics but technological advancements that explain why things are the way they are.
What happened to the paperweight?
I think one of the first gifts I ever got my dad was a paperweight. I don’t really remember if it was a classroom crafts project for Father’s Day, or if it was something I did on my own, but I found a weighty rock about the size of my hand, covered it in stamps, and painted the stamps with a thin coating of clear glue. The result was an amorphous mass with an unartistic collage of famous celebrities, American symbols, and landmarks – a paperweight.
Since then, I have never gifted anyone a paperweight. I don’t think I’ve even seen a paperweight since that time. This never really crossed my mind until I was listening to the StarTalk Radio podcast with Neil DeGrasse Tyson, and he posed the question: what happened to the paperweight? It’s not like it went out of style, especially if my tacky rock was any indicator (since it was probably more appreciated for its sentimental value rather than its elegance).
The culprit, as Tyson goes onto explain, is central air conditioning. Before central air conditioning, offices were cooled with fans. The windows were pulled wide open, and the fan would be placed strategically in an attempt to bring an insulation-removing draft through. As papers piled high in an employee’s “To-Do” box, the fans could do some damage and send papers flying through the air, a bane for all hard-working secretaries, managers, and number-crunchers.
The best way to solve this problem was to weigh the papers down with a stapler or a book or a coffee mug or more classily (sometimes), a paperweight. When fans were replaced by central air-conditioning, the paperweight went the way of the typewriter, a relic only adored by hipsters at the local coffee shop trying to prove how hipster they are (and, apparently, by one of my elementary schoolteachers, who thought that all dads needed a stamped paperweight).
How do prices of materials fluctuate over time?
This was basically a question I answered on Quora, which is an online community to ask and answer questions. The answer I put on Quora is almost identical to the answer I’ll give here, and it’s actually more economics-heavy than science or technology.
The prices of materials fluctuate periodically; sometimes increasing when supply is short and other times dropping when production technology is improved. The boring answer to describe how the trends of materials’ prices would be: it depends.
More interestingly, for example, aluminum was once one of the most expensive metals on the planet. There is a story that says that Napoleon had a dinner party, and most of his guests used gold utensils – except for his most honored guests, who were given aluminum forks, knives, and spoons. This is the same aluminum that modern 1st world citizens tear inconsequently and throw away. In Napoleon’s day, aluminum was so difficult to extract from ore, and so only the richest, snobbiest guests were deserving of aluminum cutlery. When Charles Martin Hall and Paul Héroult independently discovered that driving a current through oxidized aluminum dissolved in a molten bath of cryolite could produce elemental aluminum much more easily, aluminum supply quickly shot up, and so as economics would tell us, the price dropped.
Of course, while this is an intriguing story, the question seems to be asking more about long-term, historical prices of materials. I think that is a little more complicated. If you look up the price of gold or silver for the past few decades, you’ll probably notice that the prices increase steadily (with a few exceptions), which might be why this question was formulated. However, it’s important to consider trends in the price adjusted for inflation. Below, there is a chart of inflation adjusted prices of gold and silver. You’ll notice that there are a couple times when prices decrease over time.
These trends can typically be explained by societal and political factors. For example, the price of gold shoots up in the early 1930s. What happened during this time period? The Great Depression. President Roosevelt attempted to buy as much gold as possible for the fixed price of $20/ounce, and then increased the prices to $35/ounce so that the government could pocket the difference. The fixed price set by the US government was an artificial price and remained constant until 1971, when the US dollar was taken off of the gold standard. As such, gold and silver are kind of a strange example for pricing trends since they are used as stores of value.
So, perhaps there are other materials that can give insight into the trends of material pricing. As it turns out, the US Geological Survey keeps tabs on the cost of materials over time. Below, there is another inflation-adjusted graph of the price of a few industrial metals. Prices gradually increased from the 1950s until the early 1980s, but have trended to lower prices since then. This is attributed to better connected and highly competitive global markets.
To summarize, besides sudden changes in pricing due to advances in technology, it appears that the cost of materials is a question of economics. Supply and demand are the most fundamental factors that influence prices, and these are influenced by politics and society.