41 Fun Facts About Emerald

Emerald is a green variety of which mineral?

Beryl gave its name to the element beryllium, which the French chemist Louis-Nicolas Vauquelin found in emerald and beryl in the 1790s.

Trace amounts of which element are most often responsible for an emerald's green colour?

Vanadium can also do the job, and iron shifts the hue toward blue or yellow.

Emerald is the traditional birthstone for which month?

May: jewellers liken emerald's green to the fresh growth of spring.

Which Roman writer declared that nothing is greener than emerald?

Pliny the Elder also wrote that gem engravers rested their tired eyes by gazing at emerald's soft green.

Which Roman emperor is said to have watched gladiator fights using an emerald?

Nero: the Roman account notes that flat emeralds reflect images like mirrors, so he may have watched the fights reflected in one.

In 1779, Siamese forces carried the Emerald Buddha off from which city?

Vientiane had housed the image for over two centuries before General Chakri, later King Rama I, seized it for Siam.

Which African country is the world's second-biggest emerald producer?

Its Kagem mines near Kitwe supplied about a fifth of gem-quality output in 2004, with stones that tend to be cleaner and bluer than Colombian ones.

The word emerald ultimately derives from a Greek word meaning what?

Green gem is what Greek smaragdos meant, but ancient writers used the word for several green stones, not only true emeralds.

What French word do gemologists use for the mossy inclusions inside an emerald?

Jardin, French for garden: because nearly all emeralds have such inclusions, the trade accepts eye-visible ones even in fine stones.

What substance is traditionally used to fill surface cracks in emeralds to improve their clarity?

Cedar oil has a refractive index close to emerald's, so oil seeping into surface cracks makes them far less visible.

Unlike diamonds, at what magnification are emeralds graded for clarity?

By eye, because nearly every emerald has inclusions, so a stone that looks clean to the naked eye counts as flawless and commands top prices.

What is the shape of the signature 'emerald cut'?

A rectangular step cut: its corners are trimmed because sharp corners are weak points where a stone can crack.

Emeralds were mined in antiquity at Mount Smaragdus in which country?

Egypt's Mount Smaragdus holds the oldest known emerald mines, though archaeology dates most of the digging to Roman and Byzantine times.

Which Egyptian queen was said to be particularly fond of emeralds?

Ancient owners believed the stones sharpened intelligence, protected marriages and let their wearer see the future.

Which town is one of Colombia's three main emerald mining areas?

Muzo's emerald riches fuelled rivalries that erupted into Colombia's bloody 'emerald wars', in which thousands were killed.

What name is given to rare Colombian emeralds with ray-like spokes of dark impurities?

Trapiche emeralds take their name from the Spanish word for a sugar mill, because their dark spokes resemble a grinding wheel.

Boston's 'Emerald Necklace' chain of parks was designed by which landscape architect?

Frederick Law Olmsted combined landscaping with sanitary engineering to turn a foul-smelling tidal creek and swamp into the Back Bay Fens.

The giant Bahia Emerald reportedly survived which 2005 hurricane while stored in a US warehouse?

Hurricane Katrina reportedly hit a warehouse where it was stored; the stone was later reported stolen and traced to Las Vegas.

The emerald ash borer, a beetle that has killed millions of North American ash trees, is native to where?

East Asia: in its native range it does little serious damage, yet in North America it has killed tens of millions of ash trees.

The 37.82-carat Chalk Emerald ring, recut by Harry Winston, is on display at which institution?

The Smithsonian got it in 1972 from its owner, who reportedly turned the ring around at a White House dinner so as not to upstage Queen Elizabeth II.

Emerald Bay, site of the Scandinavian-style mansion Vikingsholm, lies on which lake?

Lake Tahoe: before building Vikingsholm, owner Lora Knight and her architect toured Scandinavia to gather ideas for the house.

Unusually for a Mughal gem, the Mogul Mughal Emerald is engraved with prayers from which branch of Islam?

Shi'a prayers: since the Mughal emperors were Sunni, the stone likely belonged not to Aurangzeb but to one of his Shi'a officers or nobles.

The Mogul Mughal Emerald belongs to the Museum of Islamic Art in which Gulf capital?

Doha's museum holds it; mined in Colombia, it was sold in India, where emeralds were highly prized by the Mughal rulers.

From which ruler did the 6th Duke of Devonshire acquire his namesake emerald in 1831?

Emperor Pedro I of Brazil had come to Europe after giving up his throne when the stone passed to the duke.

In Baum's original 1900 novel, why did everything in the Emerald City look green?

Everyone had to wear tinted spectacles, locked on with a key, and the Wizard admits the city is really no greener than any other.

Which US city has used 'The Emerald City' as its official nickname since 1982?

Seattle's tourism bureau adopted it in 1982, retiring 'the Queen City', a nickname a Portland real estate firm had given it in 1869.

Which Caribbean island is nicknamed 'the Emerald Isle of the Caribbean' for its Irish heritage?

Montserrat's St Patrick's Day is a national holiday that also commemorates a failed slave uprising planned for 17 March 1768.

The Emerald Buddha of Bangkok is actually carved from what?

The 66 cm statue is the sacred palladium of Thailand and is housed at Wat Phra Kaew in the Grand Palace.

Which Spanish conquistador reportedly had an emerald looted from Mexico engraved with a Bible verse?

The writer Brantome called the engraving sacrilege and blamed it for the man's later misfortunes.

The alchemical Emerald Tablet, source of 'as above, so below', is traditionally attributed to whom?

Hermes Trismegistus, a legendary sage, though the oldest known versions of the text are Arabic works from the 8th to 10th centuries.

Which blue gem is the same mineral species as emerald?

Aquamarine, Latin for 'sea water', gets its pale blue from traces of iron rather than the elements that turn emerald green.

What is the pink sibling of emerald within the same mineral species called?

Morganite was named by Tiffany gemologist George Kunz after his customer J.P. Morgan, one of the most important gem collectors of his day.

Which is the rarest colour of emerald's parent mineral, found almost only in Utah?

Red: traces of manganese give it that hue, and it has been sold under the misleading trade name 'red emerald'.

California's 'Emerald Triangle' is famous for growing what?

Cannabis is so woven into the region's economy that many locals rely on it directly or indirectly.

Who developed the first commercially successful process for synthesising emeralds?

Carroll Chatham showed off his lab-grown crystals but kept his growing recipe a closely guarded secret.

The 19th-century pigment 'emerald green' was made from copper combined with which toxic element?

Arsenic: the pigment, also called Paris green, went into 19th-century wallpapers whose arsenic could slowly poison the people living with them.

Which gem was as costly as ruby and emerald until huge deposits were found in the 1800s?

Amethyst was one of the five cardinal gems until large 19th-century finds in South America made even fine stones affordable.

The Greek Bible's smaragdos, ancestor of the word emerald, was one of the stones set in what?

The High Priest's breastplate held twelve stones, each engraved with a tribe of Israel's name; its smaragdos may not have been a true emerald.

How is emerald's toughness classified?

Poor, because most emeralds are full of inclusions and fractures, so despite a Mohs hardness of 7.5 to 8 they chip easily.

In gemstone grading, which of the 'four Cs' is normally by far the most important for an emerald?

Colour matters most: the finest emeralds are bluish green to pure green with vivid saturation, and a hue too yellow or blue lowers the value.

Which US body requires sellers to disclose when an emerald has been oil-treated?

Oiled stones are worth far less than untreated ones, and green-tinted oil is not accepted in the trade at all.