Gemstones are fascinating in appearance alone — these jewels are, after all, designed to be eye-catching — but behind them is a story to suit every interest, whether you’re an armchair geologist or just love pretty things. Astronomy buffs can marvel at the diamonds sparkling throughout the cosmos. For mythology buffs, there’s a teetotaling origin story that will change the way you look at amethysts. And if you have opinions on birthstones, wait until you hear how they evolved. These seven facts might just change the way you see gemstones forever.
Rubies and Sapphires Have the Same Base Mineral
Corundum is a colorless mineral that’s the second-hardest natural substance on Earth, just behind diamonds. While the average person probably doesn’t recognize this aluminum oxide in its pure form, with just a few impurities it becomes a household name. With a touch of chromium, it becomes a ruby, and just a few hints of iron and titanium turns it into a sapphire.
This isn’t a unique phenomenon. Variations of the gemstone beryl, an aluminum silicate, include emerald, morganite, and aquamarine. Some garnets are called hessonite, rhodolite, and andradite. Amethyst is a kind of quartz.
Sought-after color variations of gems like diamonds and topaz also come from impurities. Contrary to what you might think, impurities aren’t always a bad thing!
The Sun Could Someday Turn Into a Giant Diamond
Right now, the core of our sun is a hotbed of nuclear fusion. While some stars explode in a giant supernova and become neutron stars or black holes, our sun is a medium-mass star. After several billion years, it will burst into a red giant, then leave behind its core as a white dwarf.
Here’s where it gets interesting: White dwarfs are one of the highest-gravity environments in the galaxy, with a gravitational field that can be 350,000 times that of Earth’s. This compresses the oxygen and carbon of its core, causing it to crystallize. Diamonds are pure carbon that has crystallized under high pressure. (The ones on Earth formed in the planet’s core and were brought to the surface in ancient volcanic eruptions.) So while there’s some oxygen mixed in, the core of a white dwarf is essentially a diamond.
After decades of theory, in 2013 scientists actually observed this phenomena in the cosmos. Astronomers at the Harvard-Smithsonian Center for Astrophysics identified a 10 billion-trillion-trillion-carat core just 50 light-years from Earth, in the constellation Centaurus. And in 2014, astronomers announced that they’d found an 11 billion-year-old crystallized dwarf the size of Earth.
Modern Birthstones Evolve Based on Marketing
As a concept, birthstones date back pretty far, from the Christian Bible to the mystical gemstones of Hindu tradition. The tradition of wearing a stone for the month you were born began to gel in 16th-century Poland or Germany, likely due to increased trade between Europe and Asia. While these traditional gemstones certainly overlap with modern ones, there are some notable changes: March, for example, was once bloodstone, not aquamarine.
In 1912, however, the birthstone list became a wildly successful marketing tactic. The National Association of Jewelers standardized the 12 birthstones by month, choosing stones that most jewelers could produce and sell easily. That last part is key, and specific birthstones have continued to evolve over the last century.
Many classic, perennial favorites have stayed in place — diamonds for April and sapphire for September, for example. Some months shifted based on color: December has been assigned a wealth of blue stones, from the traditional turquoise and lapis lazuli to the more modern blue zircon, blue topaz, and tanzanite.
Others, like October, have shifted significantly. October’s traditional birthstone is the opal, which is still widely recognized. But in 1952, the Jewelers of America swapped in pink tourmaline to match the rest of the transparent list. As recently as 2016, Jewelers of America added spinel to the August list as part of a marketing campaign.
Amethysts Were Used as Ancient Drinking Protection
Amethysts were so widely used as wards against intoxication or hangovers in ancient times that it’s where they got their name: It comes from “not drunk” in ancient Greek. The actual mythology around the amethyst varies, but many of the stories involve Dionysus, the Greek god of wine, grapes, and drunkenness. In one version, Dionysus becomes enamored with a mortal woman named Amethystos, who was, to put it mildly, not into it. She prayed to her preferred god, Artemis, to help keep her chaste, and in response Artemis turned her into a statue of clear quartz. Dionysus either poured, spilled, or cried wine onto it, staining it purple.
So in 2021, when archaeologists unearthed an amethyst ring from the former site of — what else? — the largest known winery of the Byzantine era, they speculated that its former owner could have been trying to ward off the worst effects of drinking. The team, which had been excavating a site in modern day Yavne, Israel, said that it’s impossible to know for sure.
Garnets Were Named for Pomegranates
While it’s not quite as interesting as “not drunk,” the name “garnet” also has a somewhat decadent origin. In the 13th century, a German theologian named the gem from the Latin word granatus, which means “grain” or “seed,” in this case referring to pomegranate seeds. He wasn’t wrong: A small, oval garnet could absolutely be mistaken for a snack in the right context.
Not All Gemstones Are Stones
While most things we consider “gemstones” are minerals, in practice the distinction has less to do with chemistry and more to do with aesthetics. Calcareous concretions (pearl-like growths from certain mollusks) and pearls are the only gems to grow within living creatures. Precious coral comes from the hardened skeleton of dead coral polyps. Jet is fossilized wood. Amber is fossilized tree resin, and is one of the earliest gemstones to be carved for jewelry. All of these make fine, eye-catching stones, even if they’re missing the crystalline glint of an emerald.
The First Lab-Grown Diamonds Appeared in the 1950s
Lab-grown diamonds have grown in popularity as a more ethical and less expensive alternative to mined diamonds. These diamonds are often called “synthetic diamonds,” even though their chemical makeup is exactly the same.
After more than a century of people trying to figure out how to DIY diamonds, scientists at the General Electric Research Laboratory were the first to announce their success in 1954 — although it took them a second to figure out they did it. After they left their high-pressure equipment on overnight, a blob popped out, but it didn’t look like a diamond. They began to suspect otherwise when the material broke high-end polishing equipment, something only a diamond could do. X-ray tests confirmed their suspicions. It later turned out that Union Carbide and the Swedish company ASEA got there just slightly earlier, in 1952 and 1953, but kept their findings secret.
These small, rough diamonds were great for industrial applications, but they weren’t ready to shine just yet. Higher-quality diamonds appeared in the 1970s, although they were easy to tell apart from natural diamonds under a microscope, and hard to scale. The technology slowly improved, and in the 1990s, diamond industry titan De Beers (who played a pivotal role in our idea of the diamond engagement ring in the mid-20th century) got concerned enough to develop detection machines.
Today, most “synthetic” diamonds are made with a lower-pressure process called chemical vapor deposition, which uses heated gas in a vacuum chamber at extremely low pressures — very different from the high-pressure environment in which diamonds grow inside the Earth.
From castles, cathedrals, and palaces to miles-long bridges, golden temples, and sky-scraping glass towers, the world is full of magnificent feats of architectural engineering. While the purpose of most of these structures is known, there are still plenty of human-made monuments that boggle the minds of even the most acclaimed scientists and archaeologists. Here are 11 such monuments that remain a mystery.
Original photo by Stephanie LeBlanc/ Unsplash
Carnac Stones (France)
The Carnac Stones are a group of more than 3,000 megalithic standing stones in the French village of Carnac, Brittany. These stones date back to the Neolithic period and were probably erected between 3300 and 4500 BCE. They are one of the world’s largest collections of menhirs — upright stones arranged by humans. There is no real evidence to confirm their purpose, but that hasn’t stopped researchers from hazarding guesses. Some theorize they were used as calendars and observatories by farmers and priests. According to Christian mythology, the stones are pagan soldiers who were petrified by Pope Cornelius. Local folklore, meanwhile, says that the stones stand in straight lines because they were once part of a Roman army. The story goes on to say that the Arthurian wizard Merlin turned the Romans to stone.
Easter Island Moai (Chile)
Over 2,000 miles off the coast of Chile, Easter Island (Isla de Pascua) is the one-time home of a Polynesian people called the Rapa Nui. Scattered across the island are around 1,000 moai, giant hand-carved stone statues of human-like figures that are half-buried in the earth. The Rapa Nui landed on the island sometime between 700 and 800 CE, and are believed to have started making the moai around 1100 CE. Each moai weighs 14 tons and stands 13 feet tall on average, so it’s hard to imagine how they were transported and hauled into place. One theory is that the islanders used a system of ropes and tree trunks. Their purpose has also been the subject of much debate. To the Rapa Nui, the statues may have stored sacred spirits.
Nazca Lines (Peru)
Southern Peru’s Nazca Desert is covered with hundreds of geometric designs. These ancient geoglyphs range from simple shapes to plants and animals such as a hummingbird, monkey, llama, and whale. The Nazca Lines date back to around 200 to 700 CE, when the Nazca people who lived in the region created them. Researchers have struggled to agree upon the purpose of these giant works of art, particularly since they are best seen from the surrounding hills and by plane. Among many theories are astronomical maps, indicators of sacred routes, and water troughs. An alternative take is that they were created to be observed by deities from the sky.
Stone Spheres (Costa Rica)
In Costa Rica’s Diquis Delta is a group of around 300 polished stone spheres, some just a few inches in diameter and others measuring up to seven feet and weighing 16 tons. Employees of the United Fruit Company stumbled across the spheres in the 1930s while clearing a jungle to build a banana plantation. Scientists have so far been unable to pinpoint an exact date of their origin, instead suggesting that they appeared sometime between 200 BCE and the 16th century CE. They are commonly attributed to the Diquis people, yet their purpose is a mystery. They might have been property markers of ancient chiefs, and some even think they may be remnants of the lost city of Atlantis. Some of the spheres were even detonated in the hope of finding gold inside.
Temple of Bacchus (Lebanon)
The Baalbek temple complex in northeast Lebanon is one of the most intriguing Roman ruins on the planet. Its centerpiece is the well-preserved and monumental Temple of Bacchus. The age of the temple is unknown, although it was most likely erected in the second century CE. Most historians agree that emperor Antoninus Pius commissioned it in honor of Bacchus, the god of wine and intoxication. What has been baffling archaeologists ever since the temple’s rediscovery in the late 19th century is how the Romans succeeded in building it. It is staggering to think that humans without heavy machinery could hoist the 42 Corinthian columns (19 of which remain standing) of the colonnade, since each stands 62 feet tall and 7.5 feet in diameter.
Hagar Qim (Malta)
Located on the Mediterranean island of Malta, the UNESCO World Heritage Site of Hagar Qim is one of seven prehistoric temples in Malta and is believed to date to between 3800 BCE and 2200 BCE. The site’s name translates to “standing stones,” and one of the largest weighs in at more than 20 tons, measuring nearly 23 feet in height. The site was first excavated in 1839 and consists of a series of rooms lined by these megaliths. Parts of the chamber align with the sunrise and sunset of the summer solstice. This and the other temples on the island all appear to have been built in the same period, which has left archaeologists puzzled — there is little evidence of any civilization capable of such building feats on the islands at that time.
Göbekli Tepe (Turkey)
Could a set of ruins in southeastern Turkey be remnants of the world’s first temple? That’s one of the key questions archaeologists ponder as they explore Göbleki Tepe, a series of huge stone pillars that are some 6,000 years older than Stonehenge. Now a UNESCO World Heritage Site, the landmark was ignored for centuries, dismissed as little more than a cemetery. In the mid-1990s, excavations began and experts soon realized it was a treasure trove of history. The pillars weigh as much as 10 tons each and create massive stone circles. Radar surveys of the area indicate a number of additional circles are still buried underground. Göbleki Tepe is older than writing and older than agriculture. But who were the Neolithic people who built this, and how and why did they do it?
Yonaguni Monument (Japan)
Experts are divided as to whether the underwater rocks near Japan’s Yonaguni Island are a human-made structure or naturally occurring. In the 1980s, divers discovered what appears to be a rectangular monument, measuring 165 feet long and 65 feet wide. Some scholars believe that it is the remains of a pyramid, perhaps from a long-lost submerged city belonging to an ancient civilization. Meanwhile, others insist the rocks have been shaped by millennia of the ocean’s currents. Similarly, while some argue that markings on the rock’s surface are proof of ancient human involvement, others say they are simply scratches. For the time being, the Japanese government seems to agree with the latter and does not recognize the Yonaguni Monument as culturally significant.
Great Zimbabwe Ruins (Zimbabwe)
The Great Zimbabwe Ruins are the largest ruins in sub-Saharan Africa. This medieval city was once a trading hub and possibly the capital of the Queen of Sheba’s realm. The remains consist of the Great Enclosure (perhaps a royal residence), the Hill Complex (possibly the religious heart of the city), and the Valley Ruins (houses which suggest the city once had a population of 20,000 people). In total, the Great Zimbabwe Ruins extend across an area of 200 acres. The city is thought to have been abandoned in the 15th century, for reasons scientists aren’t sure of.
The Maya people of what is now Mexico were incredibly advanced when it came to writing, building, and knowledge of astronomy. Yet scientists still know little about other parts of their culture. By the time Spanish conquistadors arrived from Europe, the Maya civilization had already fallen, and historians still debate the cause. Some of the finest Maya ruins are at Palenque, in the Mexican state of Chiapas, an elaborate complex that includes a palace and several temples. Thought to have been constructed between 500 and 700 CE, it features plaster carvings and decorations that are still remarkably well-preserved. The city at Palenque is a marvel of design but remains shrouded in mystery since we may never know why it was abandoned around 900 CE.
No list of mysterious sites would be complete without the Neolithic monument at Stonehenge, which is known worldwide and continues to mystify visitors. The enormous stones are estimated to have been placed between 2500 BCE and 2200 BCE. Hundreds of even older burial mounds have also been uncovered in the surrounding area. Some of the stones come from several hundred miles away in Wales, leading archaeologists to speculate how they were transported. Others are from nearer parts of Wiltshire. What was Stonehenge’s purpose? Many believe it was a spiritual site, and people still flock to it as the sun rises on the summer solstice, when sunlight rises above the Heel stone at Stonehenge and falls directly onto the middle of the circle.