We can look at the history of mankind from the relationship it established with these materials over time. These materials shaped and deepened the life of human beings, created culture and raised civilizations and empires.
Human beings were first introduced to the minerals: the Stone Age was the time when man used minerals fundamentally to make tools needed for his activities. This Age is divided into three distinct periods: the Paleolithic, the Mesolithic, and the Neolithic. Then came the Metal Age which is also divided into three periods: the Copper, the Bronze and the Iron. In relation to the organic matter, humans invented agriculture, plant cultivation and pastoralism, the rearing and domestication of animals, which were used as food, working aids, transport and power.
The Organic Versus the Inorganic
In the beginning when God created the heavens and the earth, the earth was a formless void and darkness covered the face of the deep, while a wind from God swept over the face of the waters. Then God said, ‘Let there be light’; and there was light. And God saw that the light was good; and God separated the light from the darkness. God called the light Day, and the darkness he called Night. And there was evening and there was morning the first day.
And God said, ‘Let there be a dome in the midst of the waters, and let it separate the waters from the waters.’ So God made the dome and separated the waters that were under the dome from the waters that were above the dome. And it was so. God called the dome Sky. And there was evening and there was morning, the second day.
And God said, ‘Let the waters under the sky be gathered together into one place, and let the dry land appear.’ And it was so. God called the dry land Earth, and the waters that were gathered together he called Seas. And God saw that it was good. Then God said, ‘Let the earth put forth vegetation: plants yielding seed, and fruit trees of every kind on earth that bear fruit with the seed in it.’ And it was so. The earth brought forth vegetation: plants yielding seed of every kind, and trees of every kind bearing fruit with the seed in it. And God saw that it was good. And there was evening and there was morning, the third day. Genesis 1:1-13
Paraphrasing the book of Genesis, in the beginning, everything was inorganic, that is, organic matter is composed of at least two kinds of inorganic elements, three in the case of carbohydrates, and four or more depending on the complexity of the organic matter. The first, and the sine qua non condition for organic matter, is the presence of carbon atoms. The second is the presence of hydrogen atom, almost all organic compounds contain hydrogen but there are exceptions. We can say that carbon and hydrogen are the backbone of organic matter, and therefore, of life. Note that life in the account of creation in the book of Genesis appeared on the third day, in the form of plant life.
Inorganic molecules may contain hydrogen or carbon in their composition: water, for example, contains hydrogen, but is inorganic because it does not contain carbon. Carbon dioxide contains carbon but is not organic because it does not have hydrogen. Any molecule containing carbon and hydrogen is necessarily organic.
Inorganic molecules are smaller than organic, they are usually found outside of living beings, animals or plants, and do not have carbon as the main element. The fact that they are inorganic does not mean that they are not of great importance to life, take for instance the case of water, mineral salts and even some metals.
Minerals versus Metals
Concerning the differences between organic and inorganic matter, both minerals as well as metals are regarded as inorganic.
Minerals – are inorganic solid substances, and are formed naturally and spontaneously in nature, without human intervention. They may take the form of compounds or mixtures of various minerals or as one of the 118 elements in the periodic table occurring in its native form.
Minerals contain a characteristic internal structure and specific physical properties, a definite chemical composition and a crystalline structure, that is, the atoms of minerals are organized in orderly repetitive three-dimensional geometric forms. Currently, approximately 4000 minerals have been catalogued and the rate that geological studies are advancing, more and more minerals are being discovered, some of them even of extraterrestrial origin.
Metals – are solid matter with the exception of mercury which is liquid at room temperature, and they can be composites or alloys, such as stainless steel and brass, and even simple elements in the periodic table, where about 80% of the elements are classified as metals. They are hard, opaque or shiny, and are good electrical and thermal conductors. In general, they are malleable, meaning they can be hammered into thin sheet, or ductile meaning they can be drawn into wires. It is also possible to fuse them to make alloys or more defined shapes than being hammered into sheets.
Ninety-one of the 118 elements in the periodic table are metals; while the others are either non-metal or metalloid, that is, elements that have properties of both metal and non-metal.
When we say that we need magnesium or iron in our diet, this does not mean that we need to ingest the metal form of these compounds, but rather that we should consume certain foods that contain the salt of these metals. In nutrition, minerals are inorganic chemicals that we need to thrive, for tissue repair, for metabolism, and for carrying out other bodily functions.
Let us now study mineral, metal, and both organic and inorganic matter which are composed of many elements that are individually inorganic, but together they form the basis of life.
Minerals
As was mentioned earlier, minerals are inorganic solid matter that are formed naturally in nature, and they have a definitive chemical composition, as well as an internal crystalline structure. In minerals, the specific atoms are generally arranged in an ordered internal structure with an established chemical chain responsible for giving this mineral its physical properties.
It is made up of the same chemical composition throughout. The 4000 or so minerals identified, each has a unique set of physical properties, and are classified according to colour, streak, luster, cleavage, hardness, reaction to acids, the shape that it maintains when fractured, transparency, density and electrical properties. As to their nature, minerals are divided into two main groups: the silicates which make up more than 90% of the earth’s crust, and the non-silicates which are subdivided into carbonates, sulfides, oxides, sulfates, halides and phosphates, and native elements such as gold, silver, copper ores.
‘Organic’ Minerals
As we have already mentioned, all minerals have inorganic origin but some substances are better viewed as organic minerals. What I mean by this is that there are compounds or solid matter that appear to be minerals, like pearl and amber, but we know have organic origin.
Pearl is formed when a foreign body or irritant, like a parasite or a grain of sand, enters into an oyster, mussel or clam. In order to defend itself, the mollusk secretes a substance called nacre or mother of pearl, the same material that lines the inner walls of the shell. The mollusk wraps the irritant in layers of nacre, and in this way, gets rid of the problem and heals the wound made by the irritant. The pearl is basically a healed wound.
Amber, on the other hand, is of plant origin. It is fossilized resins produced millions of years ago by various types of trees that are now extinct.
Rocks
These are composed of two or more minerals and are classified based on the presence of the most abundant one. As far as the formation process is concerned, there are three main classes of rocks: igneous or magmatic, metamorphic and sedimentary. The earth’s crust is made up of 80% igneous or magmatic, 15% metamorphic and only 5% sedimentary rock.
Igneous or Magmatic Rocks – These are rocks that are formed from the cooling and hardening of magma or lava. They are therefore crystallized from a liquid, beneath the earth’s surface from magma or at the earth’s surface from lava. The rate of cooling of the melt determines the texture of the igneous rocks, with fast cooling yielding small fine-grained crystals while slow cooling allowing large crystals to form resulting in coarse-grained crystals. Lava cool quickly at earth’s surface while magma cool and crystallize slowly. For example, basalt is a fine-grained igneous rock which leads us to conclude that it is formed by rapid cooling of lava at the earth’s surface.
Metamorphic Rocks – These are rocks that formed from the physical or chemical alteration of other rocks, igneous or sedimentary or another older metamorphic rock, as the result of extreme pressure and heat. This means that all metamorphic processes involve solid state transformation of existing rock types in a process known as metamorphism, or “change in form”. In other words, the creation of a metamorphic rock requires that the transformation of the pre-existing rock has not undergone lithification (transformation into magma) or sedimentation (breaking rocks into particles).
Sedimentary Rocks – When rocks undergo erosive processes, such as from the action of water and wind that “shatter” them into small particles, sediments (like the sand on a beach) are formed. These sediments, in turn, are deposited in the lower relief zones and as they clump together they can form new rocks, called sedimentary rocks. For example, limestone that exists in the coastal regions are formed by the accumulation of shells, corals, and bodies and parts of dead aquatic organisms is simultaneously a sedimentary and organic rock.
Ore – Rocks have minerals and when these occur in large concentration they are called ores. Ores are mined for metals like iron, copper, or non-metals like talc. Ores are minerals containing metals that have great economic value, which justifies their extraction. Iron, for example, is taken from a mineral called hematite; therefore, hematite is the iron ore. Aluminum is extracted from an ore called bauxite, while lead is extracted from an ore called galena.
Does this mean that metals are minerals? Recalling the definition of mineral above, we know that it is any inorganic, solid, and naturally occurring compound that has a crystalline internal structure and a definite chemical formula. Now metals are indeed inorganic, solid, and most have crystalline structures; but do they occur naturally? There are metals like gold that can be called mineral and metal at the same time because they are found in nature in their metal form and not from a melted mineral.
The Stone Age
For their activities, human beings needed tools. The provenance and nature of these tools have been changing with a gradual increase in complexity over time. Not having yet discovered metal, humans began by making tools out of stone. The Stone Age is, therefore, the time where stones were used as the preferential tool, in addition to tools from animal bones and wood. This great period began two and a half million years ago, and lasted until the end of the second or last Ice Age, around 9600 BC. It is divided into three different periods: Paleolithic, Mesolithic and Neolithic.
Paleolithic – or Old Stone Age, is a period where humans survived exclusively from hunting and gathering of fruits and plants; they were nomads, going from place to place searching for food.
Mesolithic – this is a transition period, in which in addition to hunting and gathering vegetation, humans learned to fish; they were still nomads.
Neolithic – or New Stone Age, the great revolution of this period was the introduction of agriculture and animal husbandry. Propelled by shortage of food, human intelligence replaced the gathering of fruits with agriculture and hunting with animal domestication and husbandry. The appearance of the first settlements started and humans ceased to be nomadic. This period lasted until 4000 BC.
The Nature of Metals
Unlike minerals, the internal crystalline structures of metals are less static: since the atoms of metals are in close proximity to one another, the outer electrons of the atoms have great mobility, being attracted simultaneously to the nuclei of neighbouring atoms. In this way, they are no longer tightly bonded to a specific atom, but are free to wander through the entire metal.
It is for this reason that metals are malleable and good conductors of heat and electricity. We need to recall when we talked about atom, that the electrons are the most active part of an atom, and that atoms are linked to one another via their electrons to form compounds.
The Characteristics of Metals
Conductivity – metals are by nature good thermal and electrical conductors.
Malleability – they are very malleable, especially when subjected to high temperatures.
Elasticity – they are susceptible to deformation or shape changing when subjected to external actions.
Ductility – this is the ability of metals to be stretched to form cables and wires.
Luster – in general, metals are not dull but can reflect light very well from their surface, and can be polished.
The periodic table of elements does not, so to speak, recognize minerals as it divides its 118 elements into metals, non-metals and metalloids. As already mentioned, metals are malleable and good thermal and electrical conductors. Non-metals, on the other hand, are poor conductors of heat and electricity, and are not easily bent, like carbon, nitrogen, phosphorus, oxygen, sulfur, selenium, fluorine, chlorine, bromine, iodine and astatine. Metalloids have both metallic and non-metallic properties, examples are boron, silicon, germanium, arsenic, antimony and tellurium.
Our Everyday Metals
Metals can be divided into ferrous metals like iron and steel, and non-ferrous metals like aluminum, copper, tin, nickel, brass and bronze.
Copper – it is used particularly in electrical equipment such as motors, circuits (cables, switches etc.). They are also coins made of copper.
Iron – it accounts for about 95% of the world’s metal production, and is widely used in cars, boats, and buildings due to its low cost and high strength. It is sometimes replaced by steel when a higher hardness and strength is required.
Zinc – it is used widely in the production of brass and due to its low cost, it was used for a long time to make bowls; it is still used to cover the roofs of rural homes in Africa, in place of straws.
Tin – it is principally used in alloys, such as bronze, the bell metal (copper and tin), phosphor bronze, soft solder and pewter. It is also essential in the production of glass, soaps, perfumes, paper, medicines and fungicides. The sheets wrapping chocolates or cigarettes, for example, also contain tin.
Aluminum – it is used in windows and in structures where the resistance of iron is not necessary, aluminum is used because it is lighter.
Nickel – it is widely used in the fabrication of coins.
The Metal Age
With the introduction of agriculture and animal husbandry, human beings became less dependent on nature, freer and more independent, thus with more free time to think. The tools invented completely changed with the discovery of metals. The metals that were discovered defined three periods: Copper, Bronze, and Iron.
The Copper Age (3200 - 2300 BC) – possibly the first discovery of a metallic material occurred by chance, when the stones that used to contain bonfires contained copper oxide and were reduced to metal by the heat. This will be the beginning of the extraction in metallurgy, based essentially on empiricism and in the direct and personal transfer of knowledge. Since copper is not very hard, the first use of this metal was in ornaments.
The Bronze Age (2300 – 700 BC) – bronze is an alloy or a mixture of two metals, primarily of copper with tin. Both metals are not very hard and are very malleable, yet together they form bronze which is a hard metal. Because of its hardness, bronze was not used for ornaments, but rather in agriculture tools, domestic utensils, and for weapons.
The Iron Age (1200 BC) – lastly the Iron Age, a metal that is more common than the previous two, and the last one to be discovered. The Earth’s crust is composed of 5% iron. As we have said above, this is the metal most used by man, since its discovery until today. Hence we can say that we are still in the Iron Age.
Organic Matter
As we have seen, the boundary between organic and inorganic matter is not always very clear.
- In general, organic compounds are produced by living organisms, inorganic compounds are produced by nature or man-made.
- Inorganic compounds can form salts, organic compounds cannot.
- Organic compounds always contain carbon, inorganic compounds do not.
- Organic compounds contain hydrogen-carbon bonds, inorganic compounds do not.
- Inorganic compounds contain atoms of metal, organic compounds do not.
Soil Composition
The soil or land that covers most of the Earth’s surface, with the exception of rocky surface, is also composed of particles that belong to three different classification:
Sand particles – are the largest of the three types of soil particles. Sandy soil has up to 80% sand; this type of soil do not retain water and nutrients well, so it has a very low value for life.
Silt particles – are the next largest soil particles, they make up the sludge or sediments. Soils with high silt content are found along riverbanks and are the most fertile in the world.
Clay particles – are the smallest of the three soil types, hence retain water the best but run the risk of becoming waterlogged, making it difficult for plants to grow. Therefore both clay and sand particles are not very fertile.
Fertile Soil
In addition to the three types of particles that make up all kinds of soil, good soils that are fertile rely on water and air, that is, on moisture and aeration. The amount of sand that the soil contains allows for the presence of air, the sand particles separate the organic matter and the clay, making it possible for air to enter. The quantity of clay allows for the presence and retention of water.
The humus that all fertile soil must contain, results from decomposition of plant residues and animal carcasses by the action of microorganisms. Humus is, in fact, the final result of this decomposition and confers a high degree of fertility to a soil; we can conclude that life feeds on life. It is nature that recycles itself and it is life that is diversified. The ideal soil for agriculture, which human beings discovered in the Neolithic Period, should be made up of 45% minerals (sand, silt, clay), 25% water and 5% organic matter.
The Chemical Composition of the Human Body
The human body is formed by the interaction of the same elements that make up the universe; it is therefore a micro-universe in itself.
Present in large quantities
Hydrogen, carbon, nitrogen, oxygen – are the constituents of substances present in the body in large quantities (sugars, proteins, fats etc.). Among them, hydrogen and oxygen form water which is responsible for more than half of the mass of a human body.
Present in smaller quantity
Sodium – present in blood and in other bodily fluids.
Magnesium – plays an important role in muscle function and in calcium synthesis.
Phosphorus – present in phosphate which allows for energy storage.
Sulfur – participates in the composition of some proteins.
Chlorine – present in blood and other bodily fluids.
Potassium – present in blood and other bodily fluids.
Calcium – constituent of bones and teeth.
Present in trace quantities
Fluorine – is part of teeth enamel that prevents cavity formation.
Chromium – participates in sugar metabolism.
Manganese – participates in the metabolism of sugars, fats, and in bone formation.
Iron – a component of hemoglobin, a pigment that carries oxygen in the blood.
Cobalt – part of vitamin B12 composition, which helps keep the body’s nerve and blood cells healthy.
Copper – helps in the occurrence of some chemical reactions.
Zinc – necessary for normal growth.
Selenium – aids in digestion and assimilation of oils and fats.
Molybdenum – helps in the occurrence of some chemical reactions.
Iodine – important for proper thyroid function.
The body or matter of a living organism is a complex and mysterious combination of organic and inorganic materials; with each organic material being in itself composed of simpler inorganic elements. Some of these simpler inorganic elements, on their own, that is, without being part of organic compounds, are needed for life to exist and to process itself. Examples of these are water and oxygen.
Inorganic materials therefore concur twice to make life possible. First, they are part of the organic materials that form the matter or body of a living organism, and second, they facilitate, support and make possible the life of that living organism. So, inorganic matter not only make up the core of the body or matter of a living organism but they also, at the same time, facilitate, promote and create the environment where the living organism thrives.
Fr. Jorge Amaro, IMC
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