The story of materials

by Jason Crawford · September 3, 2017 · 3 min read

A summary of what I have learned so far about the story of materials. I still have a lot to learn here, but a picture is emerging.

The story of materials is a part of the story of manufacturing, which is what I’m calling the general area of technological and economic development that can simply be understood as “making things”. “Manufacturing” itself, in this definition, is one of five broad areas that I’ve identified in my overall study of material progress.

Stone Age

In pre-historic tribes, people used the materials provided to them by nature. Having no settled society and no division of labor to speak of, there was little opportunity to process materials in any but the most rudimentary of ways. So, they were limited to:

• Stone, which they fashioned into tools for cutting, breaking and scraping
• Wood, in its natural form (sticks, branches, tree trunks)
• Animal products: skins, bone, perhaps organs (such as a bladder used as a pouch)
• Other plant products, such as vines, grass or straw for weaving

With scant materials and little time, and subject to the constraints of a nomadic existence, there were only a few kinds of things they could make:

• A limited number of small goods, mostly tools & weapons
• Primitive clothing from animal skins
• Maybe some simple shelters, like a lean-to
• Basic watercraft, such as rafts or dugout canoes

Agricultural Age

Starting with the advent of agriculture and settled societies about 10,000 years ago, people had time and space to experiment with new ways of processing materials and to accumulate capital equipment for doing so, from furnaces to mills. In this period, even before the Industrial Revolution, mankind developed most of the basic materials of the modern world.

I see five major categories of general-purpose materials from this era (a sixth was added in the Industrial Age):

• Metal, especially iron and copper (and their alloys, such as steel and bronze)
• Wood, now in mass-produced form (timber)
• Stone, now used less for tools and more for construction
• Clay, baked into bricks and fired into pottery
• Glass, typically blown

This is not an exhaustive categorization. Rubber, for instance, is an important (if minor) general-purpose material, but it doesn’t really fall in any of the categories above. (I am not sure that an exhaustive categorization is useful.)

I call these “general-purpose” materials because they can be used for a variety of important products. There were also a few special-purpose materials, used mainly for one kind of product, that are important enough to deserve mention:

• Textiles, especially cotton and wool, for clothing and other fabrics
• Paper, a specialized wood product
• Concrete, which could almost be considered a liquid form of stone

With these new materials, and thanks to a division of labor, we made many more things, such as:

• A much wider variety of small goods, espeically out of metal
• Clothing from textiles
• Buildings and infrastructure
• Many kinds of vehicles: carts and wagons, boats and ships, eventually carriages

Industrial Age

In the Industrial Age, we have mostly kept using all the same materials as before, but:

• All the materials got cheaper and at the same time higher quality, especially metals, due mainly to improved processes.

• We made a wider variety of special types of materials, such as alloys, with different properties.

• We created machines to do a lot of the work for us, which again reduced labor (and therefore cost) and improved consistency and quality.

(In metal and glass, processes seem to be most important; in textiles, I think it was the machines.)

We also invented one major new material: plastic. Plastic is a wonder material with amazing properties. It is light, but can be made strong. It can easily be made into any desired shape through a variety of manufacturing techniques. It can be made rigid or flexible. It can be made any color, even transparent. And it’s extremely cheap. This combination of properties led to it replacing metal, wood, clay and glass for many applications. (We’ve even made new textiles out of it.)

Finally, an entire new industry arose—electronics—that required new properties of materials (such as conductivity or resistance), and that ultimately gave rise to a whole class of special-purpose materials: semiconductors.

In each age, as certain materials arise, most of the other ones continue to be used, but some fall away. We don’t use animal bladders as water pouches anymore. And some become luxury goods, like leather and ivory, because animal production couldn’t scale (this was a significant motivation for the invention of plastics.)

Social media link image credit: Jeff Kubina from Columbia, MD (CC BY-SA 2.0)