Silicon, a cornerstone of modern technology and natural wonder, offers 10 remarkable uses that touch everything from the chips inside your phone to the glitter of a gemstone. Its status as the eighth most abundant element in the universe means it quietly underpins much of the world we experience, whether we realize it or not.
1 A Design For Life?
Silicon‑based life may sound like the plot of a sci‑fi novel, but scientists actually entertain the notion that life could arise from silicon rather than carbon. Carbon’s four‑valent nature makes it an ideal building block for Earthly organisms, and silicon shares that tetravalent characteristic, giving it theoretical potential as a biological scaffold.
Nevertheless, silicon chemistry diverges from carbon in critical ways. Silicon chains are far less stable than carbon chains, and silicon’s strong affinity for oxygen means that any silicon‑based respiration would have to contend with silica formation, a process that would likely choke out life as we know it. While the odds of silicon‑based organisms thriving on our planet are slim, the possibility of such creatures lurking on distant worlds remains an open question for astrobiologists.
Benjamin Thomas, a writer from Britain, delves into the speculative realm of silicon life, reminding us that the universe may still hold surprises far beyond our carbon‑centric expectations.
2 The Roundest Object In The World
At the Australian Centre for Precision Optics in Sydney resides a silicon sphere that claims the title of the roundest man‑made object on Earth. Engineers painstakingly polished the sphere to such an extreme degree that, if it were the size of our planet, the highest peak and deepest valley would differ by merely 14 metres (46 ft). The raw silicon alone cost roughly one million euros.
This marvel, part of the Avogadro Project, was crafted to aid in redefining the kilogram. For over a century, the kilogram was anchored to a platinum‑iridium cylinder stored in a vault beneath Paris, known as “Big K.” However, subtle mass changes in that artifact prompted the search for a more stable standard, leading to proposals that included this silicon sphere.
Although the sphere ultimately lost out to a watt‑balance method for the 2019 redefinition of the kilogram, its creation showcases silicon’s capacity for precision engineering on a scale that borders on the astronomical.
3 Diatoms
Encased in siliceous shells, diatoms represent a vast group of microscopic algae that populate oceans, lakes, and rivers worldwide. Their protective walls, called frustules, are constructed from silica—the same material that gives opals their sparkle—and feature intricate, lattice‑like patterns that have earned them the nickname “jewels of the sea.”
A frustule consists of two overlapping halves: a larger epitheca and a smaller hypotheca. When a diatom reproduces, these halves separate, each serving as a scaffold for the formation of a new complementary half. Over successive generations, the organism’s overall size diminishes, sometimes shrinking up to 60 % within months.
To avoid vanishing from continual size reduction, diatoms generate specialized growth spores that reset their dimensions, ensuring the lineage persists across countless cycles of division.
4 Terracotta Army
The famed Terracotta Army of China, famous for its life‑size clay soldiers, also hides a surprising connection to modern physics through a pigment known as Han purple. This synthetic hue, made from barium copper silicate, was employed during the Han dynasty to color some of the clay figures.
When chilled to near‑absolute zero, Han purple exhibits an exotic quantum phenomenon: magnetic waves traversing the material lose one spatial dimension, effectively converting three‑dimensional propagation into two‑dimensional behavior. Researchers at Stanford have suggested that studying this effect could inspire advances in quantum‑computing technologies.
Archaeologists believe the pigment arose unintentionally as a by‑product of early glass‑making techniques, demonstrating how ancient craftsmanship can intersect with cutting‑edge scientific inquiry.
5 Opals
Opals, treasured by royalty and collectors for centuries, derive their dazzling play‑of‑color from silica spheres packed tightly together within the gemstone. This microscopic arrangement refracts light in a phenomenon called opalescence, producing a shifting rainbow of hues that change with the viewing angle.
Historical figures have long coveted opals: Roman senator Nonius faced exile after refusing to sell a prized opal to Mark Antony, while Queen Victoria and her daughters frequently wore opals, gifting them to newlyweds. Napoleon even presented his wife Josephine with the famed “Burning of Troy,” a vivid crimson opal.
Pliny the Elder extolled the gem, writing that opals combine the fire of rubies, the purple of amethysts, and the green of emeralds, rivaling the palettes of painters and the glow of burning sulfur.
6 Silly Putty
During World War II, the Allied powers found themselves cut off from natural rubber supplies after Japan seized the Indonesian rubber plantations. The shortage spurred a frantic search for a synthetic alternative.
American chemist Earl Warrick, who later helped develop silicone rubber, mixed silicone oil with boric acid and inadvertently produced a strange, non‑Newtonian fluid. Independently, General Electric engineer James Wright stumbled upon the same material. The resulting compound behaved like a solid when struck but flowed like a liquid under gentle pressure—a property now recognized in substances such as custard, paint, and ketchup.
Although Silly Putty became a massive commercial hit, neither inventor profited substantially. Businessman Peter Hodgson bought the production rights, amassing millions, while Warrick, despite holding the patent, received only a single dollar.
7 Communicating With Extraterrestrials
When Apollo 11 touched down on the Moon in July 1969, the astronauts left a small silicon disk—about the size of a fifty‑cent piece—among the flag and plaque. Engraved on the disk are 73 goodwill messages from world leaders, including President Richard Nixon, Pope Paul VI, Queen Elizabeth II, Emperor Haile Selassie I, and Canadian Prime Minister‑designate Pierre Trudeau.
To fit the messages, the lettering was reduced 200‑fold, rendering it smaller than a pinhead. The disk also bears the names of U.S. presidents and a top inscription reading, “Goodwill messages from around the world brought to the Moon by the astronauts of Apollo 11.”
Because lunar surface temperatures swing between +121 °C (250 °F) and –173 °C (–280 °F), the disk’s silicon composition had to endure extreme thermal stress. The etching technique employed mirrors the photolithography used to fabricate integrated circuits, showcasing silicon’s versatility beyond Earth‑bound electronics.
8 Medical Silicone
Beyond its pure elemental form, silicon gives rise to a family of compounds, most notably silicone rubber—a flexible, temperature‑resistant polymer created by combining silicon with carbon, hydrogen, and oxygen. Since the 1960s, silicone rubber has become a staple in aerospace, electrical, and industrial applications.
The medical field has embraced silicone for a variety of devices, including hearing aids, drainage tubing, and balloon catheters. Its biocompatibility and chemical inertness also make it a popular choice for breast augmentation, where silicone gel‑filled implants offer a natural feel and reduced risk of deflation compared with saline alternatives.
It’s a curious juxtaposition: a material that seals aircraft components also serves as a cornerstone of cosmetic surgery, underscoring silicon’s remarkable adaptability.
9 Plant Growth
Silicon ranks as the second most abundant element in Earth’s crust, trailing only oxygen. Naturally occurring in soils, it is absorbed by a range of broadleaf plants and grasses, though it is not essential for plant survival.
Research indicates that silicon can bolster plants under stress, enhancing drought tolerance and extending the period a plant can survive without water before wilting. In staple crops such as rice and wheat, silicon fortifies stem strength, reducing susceptibility to weather‑induced damage.
Additionally, silicon appears to improve resistance to certain fungal pathogens. However, moderation is key: excessive silicon can damage the flowers of sunflowers and some daisies, highlighting the need for balanced application.
10 Semiconductors And Microprocessors
Semiconductors have reshaped the modern era. Every time you fire up a gadget, stream a video, or swipe on a smartphone, you’re relying on silicon‑based semiconductors to process signals and power functions. The very device you’re reading this on likely houses a silicon microprocessor packed with billions of transistors.
Silicon’s atomic structure makes it ideal for high‑performance computing. Pure silicon crystals act as insulators, but when doped with trace amounts of other elements, they become “semi‑conductors,” allowing controlled electricity flow. This dual nature gave rise to Silicon Valley—a moniker for the Santa Clara region that now hosts tech titans like Intel, Apple, Facebook, and Uber.
The simplest semiconductor component is a diode, which permits current in one direction while blocking it in the opposite. More complex transistors, the building blocks of modern microprocessors, can be viewed as sophisticated multi‑diode arrangements, enabling the rapid calculations that drive today’s digital world.