To get a broad idea where to look for resources to make things one should first have a broad idea what things are actually mostly made of. Naturally the stuff that is most abundant is used in the biggest quantities.
- 1 What elements are things made of today (2017)?
- 1.1 Rock like – Non combustible materials
- 1.2 Volatile element materials – Easily combustible materials
- 1.3 Rock like non combustible despite volatile element containing
- 1.4 Metals in metallic state – Somewhat combustible slack forming materials
- 1.5 Remnant elements in burnt waste (landfill material)
- 2 The major material reservoirs of earth
- 3 Scarce elements
- 4 Solar system
- 5 Kinds of abundance – occurrence vs accessibility
- 6 Related
- 7 External links
What elements are things made of today (2017)?
First and foremost there are loads and loads of oxygen almost everywhere on earth and even in the solar system. (Deep planetary cores and metallic asteroids are an exception). In large part the oxygen occurs bond to hydrogen as water H2O. Its simpler to mention oxygens rare absence instead of its presence.
The following examples of material usage today (2017) and here (on earth) are sorted roughly by decreasing usage quantity and classified by character.
Rock like – Non combustible materials
Materials that can be found in long lasting housing are: e.g. clay (bricks) and other silicates (in form of sand, gravel or amorphous glass) In more detail:
- Quartz & glass: oxygen, silicon
- Clay: oxygen, aluminum, silicon
- Other silicates: oxygen silicon, calcium, magnesium
Dishware (clay and ceramics, glass bottles, ...) contains the same elements and can be counted to this class. It makes up a vanishingly small volume in comparison though.
Volatile element materials – Easily combustible materials
All the stuff we make from crude oil is mostly out of carbon and hydrogen. It's all hydrocarbons chains. We make three main things out of crude oil. Asphalt, fuel, and plastics. Asphalt is silicate gravel (mentioned in the section above above) mixed with bitumen (pure hydrocarbon). Increasingly refined crude oil makes our fuels: Kerosene, heating oil, diesel, gasoline, ..., (butane, propane, ethane, methane).
The first class of rock like materials is incombustible (it is saturated with oxygen). The second class of hydrocarbon materials is fully combustible. That is: after combustion there are no solid remnants (at earth temperatures). In other words when these materials are saturated with oxygen the are no longer solid. They are gaseous. They are made from "volatile elements". They are not slack forming when combusted but instead form gases. The most relevant of these ash-gases is our infamous problem child: carbon dioxide. The reason why these materials with such highly energetic "unstable" state do even exist is thanks to prehistoric life (alien looking carboniferous scale trees) that dragged down these volatiles into the solid state (coal, later crude oil and natural gas).
Today's biomass is too of this second combustible class. It includes: soil, plants, wood, animals, food, paper and humans (sorted roughly by falling volume again). Biomass is mostly made out of just four elements: carbon, hydrogen, oxygen and nitrogen (fertilizer).
- burnt hydrogen = Water
- burnt carbon = carbon dioxide ... + water => carbonic acid (mild) –– CO2 makes the majority!
- burnt nitrogen = nitric oxides NxOy ... + water => nitric acid (aggressive)
- (burnt oxygen = joins the force of the attacking oxygen but provides less or no energy)
- burnt sulfur = sulfuric oxides SxOy ... + water => sulfuric acid (aggressive)
- burnt chlorine = very aggressive and poisonous volatile compounds
Solid ash (exception here):
- burnt phosphorus: phosphor oxides ... + water => phosphoric acid
Rock like non combustible despite volatile element containing
In long lasting housing one also finds the not yet mentioned limestone. It can be found both in the form of natural gravel and in the form of hardened cement in concrete.
- Limestone: oxygen, calcium, carbon
- Cement: Same as limestone plus additives containing also: aluminum, silicon
(web-link: composition of concrete)
As one can see from the combination of elements (calcium and carbon) limestone lives in an intermediate world. Calcium is capable of making the carbon nonvolatile even if fully oxidized.
Metals in metallic state – Somewhat combustible slack forming materials
In transportation we find ships, trains, rails and cars. All these are to a good deal made of metallic iron. Note the absence of the omnipresent oxygen! This iron is dwarfed by the amount of iron used in housing though. But in housing iron is present a rather minor fraction and was not mentioned there for simplicity.
- In contract to carbon iron rarely occurs as unoxidized as native element mineral. Instead of relying on prehistoric nature we have do do the reverse burning process (reduction) ourselves.
- In contrast to carbon iron is really unstable and (unlike plastics) quickly rusts away when pure.
metallic titanium is an odd one. Despite its extreme abundance on earth it is very hard to extract and process with current technology. Giving it a high price and limited usage (e.g. in medicine as hip joint replacement). Same goes for the a bit less abundant element zirconium (right below titanium in the periodic table).
Metallic copper despite its wide and visible use on roofs and for wiring is already quite rare. The same goes for zinc and tin that are often used for decorative items (figurines, cups) either pure or as alloyed with copper to brass and bronze respectively.
- In convenience stores one finds metals in the form of the frequently disposed of food and beverage cans (aluminum, iron).
- In the kitchen one finds the rarely disposed of pots, pans and eating utensils.
- In the workshop one finds metals in power tools in the form highly alloyed steels.
Due to low production volume and long term use much more rare alloying elements are used in high concentrations like: chromium, nickel, copper, silver, manganese, vanadium, molybdenum, cobalt, ...
Remnant elements in burnt waste (landfill material)
Burnt trash can be abundant in rare elements.
As we all know throwing everything together results in a horrible recycling nightmare. Especially problematic in recent years became electronics (and lamps). They contain a wide range of valuable (since rare) but problematic materials in a finely intertwined way that makes separation very hard.
The amount of rock-like non-burnable slack remaining after burning combustible waste depends on the the quality of waste separation. (In some countries, like e.g. Japan, combustible and non-combustible waste is strictly separated)
Since our current residual waste is mostly made out of combustible volatile elements (at least in some parts of the world - as of 2017) it is easy to enormously reduce this part of the waste in volume by burning it. Combustion of almost (but not completely) volatile waste concentrates the few non-volatile trace elements. These usually are mostly alkali metals, but also poisonous heavy metals. (natural radioactivity gets concentrated a lot too btw)
The reason for the poisonousness or the more rare trace elements may lie exactly in the fact that they are rare and biology thus never had to learn to deal with them in high concentrations.
When unprocessed ash from burned trash is dumped out in the open on unprotected ground, then the rain converts this ash into aggressively basic (alkaline - low pH) and the poisonous soup containing loads of otherwise valuable rare metals seeps into the ground and spreads in the ground water and biosphere.
If even a moderate amount of incombustible (or semi burnable metallic) trash is thrown to the combustible trash separation of the valuable remnant elements (now or in the future) becomes much harder. (Try to avoid that.)
We cannot run out of rare elements on earth unless we shoot them into space. We can though make them inaccessible for an inconveniently long time. Unaccessible till we finally reach a technology advanced enough to allow us to sieve through this highly diluted waste with sufficiently high efficiently to make it economical again.
The major material reservoirs of earth
Carbon & Biosphere (soil)
On earth carbon is widely distributed through its layers
- in the atmosphere as CO2
- in the biosphere as humic substances
- in the lithosphere as fossil oil and as carbonates (e.g. calcite)
- maybe there are some abiotic carbon remnants from before the time there was life on earth that never cycled through the biosphere
Albeit carbon is rather rare relative to silicon (silicon is the second most abundant element in earth's crust right after oxygen) it has been highly concentrated in the topsoil by biological activity on earth. Albeit easily reachable at many places this carbon should probably not be extensively used as a resource for permanent conversion to the mechanosphere since this carbon forms a very core part for all life on earth.
If not blown into the atmosphere as CO2 fossil oil (from the berried ancient biosphere) is fine to use as building material. Especially with vastly improved more environmentally friendly mining techniques. As long as there's enough CO2 in the atmosphere this would be the ideal source though.
- N2 O2 H2O Ar CO2
The elements easiest to attain are not equal to the most abundant ones. E.g. Nitrogen - albeit it's relative scarcity - is easier to get than Silicon or Titan since it can be drawn from the atmosphere. Given a bit of patience carbon can be drawn directly from the atmosphere too. Carbon has an already existing infrastructure for delivery too: gas pipes. Read the "air as a resource" page for further information.
Interesting fact: The mass of carbon humanity put in the atmosphere till now (2017) far exceeds the mass of concrete in all of the cities on the entire earth together.
(TODO: calculate the mass of human made CO2 in the atmosphere and compare it to the mass of concrete in all the cities worldwide)
The most common elements on the earths surface are the ones found in rock forming minerals: Most contain silicon as the main ingredient.
Wikipedia: the abundance of elements in earths crust
(wiki-TODO: add graphic showing relative abundances of elements in colored boxes)
Salts in the sea (alkali metals and halogenides) are a huge reservoir of potential building material but unfortunately with view exceptions simple compounds of those elements make no good building materials. Exceptions are:
- Periclase MgO
- Fluorite CaF2,
- Sellait MgF2)
- Magnesium Diboride MgB2 (superconductor, health hazard)
- Calcium Hexaboride CaB6 (barely dissolvable but irritating)
Other compounds tend to strongly dissolve in water (that was the reason why they where in there to begin with) and are often brittle due to their ionic salt like bonding structure. More complex compounds are often more water stable but also structurally rather weak (maybe due to weak hydrogen bonds).
With AP Technology many if not all scarce elements can be replaced by a few abundant ones
- (augmented) carbon nanotubes can replace copper cables and soldering tin
- artificial motor-muscles can replace electrical motors that use rare earth elements
- interferometric displays or AP quantum dots can replace indium in screens
- chemomechanical converters can replace metal using rechargable batteries
- production of microchips - metal and poison free
- no scarce alloy metals (e.g. Mo,Cr) for steel in cars are needed
A huge part of the current (2014..2017) focus of material science research is on metals (even beside metallurgy). In part this may be because of the relatively high count of metals in the periodic table and their interesting magnetic properties.
In a future time where metamaterials out of abundant element gemstone material can replace most scarce metals lots of metallurgy knowledge may become obsolete but other parts of knowledge about metals will maybe find some applicability in niche areas like quantum computing.
(wiki-TODO: add graphic of sun distance dependent elemental abundance - rough sketch)
Kinds of abundance – occurrence vs accessibility
"Abundance" of elements (or materials and products made from them) can be interpreted in two ways:
- abundantly occurring elements (always relative to the body one averages over)
- abundantly accessible elements
One kind of abundance does not imply the other kind. Neither in one or the other direction. Charts usually show the "abundance in occurrence" but what is actually of economic interest is the "abundance in accessibility". Mining is always (per definition perhaps) conducted at the locations where the resource of interest is most abundantly accessible.
Examples for all four combinations:
- Oxygen, being present in the majority of rocks and in the atmosphere, is both abundantly occurring and abundantly accessible
- Both carbon and nitrogen are not abundantly occurring on earth but those elements are concentrated in the biosphere (and atmosphere) and thus abundantly accessible.
- Titanium (and to a little lesser degree zirconium) is abundantly occurring on earth but is hard to extract and process with current (2017) technology. Thus it is not abundantly accessible. In the case of aluminum conventional (non AP) technology has already reached a level that makes large scale extraction economically possible to a very low price. It is now abundantly accessible. Extraction from silicon containing rock (majority of all rock) is still not economical though.
- The heavier noble gases (except argon) and some noble metals (on Earth) are not abundantly occurring obviously. But they are not abundantly accessible either in comparison to most other elements. Well, concentrations of noble metals in native-metal-nuggets in ore-veins (veins that potentially/usually contain other valuable elements in much higher quantities) and collection of noble gases in hydrocarbon pockets raise accessibility.
The more rare rare-earths-elements more to the right in the periodic table (not the abundant rare-earth-elements more to the left) are highly diluted and difficult to extract (due to chemical similarity). Thus they too make a good example of neither abundantly occurring nor abundantly accessible elements.
- Resource scarcity, Scarce elements
- Periodic table of elements
- Chemical element
- Local resources vastly vary with the location in the solar system. See: Colonization of the solar system
- Also classified by the "...spheres": Geoengineering
- Wikipedia: Topsoil (carbon rich!)