Ruby Trivia
0Loading crowd target
0Loading crowd target
6correct to beat the crowd
58 free Ruby trivia questions with answers — nature quiz, new questions added Sep 2026.
This ruby trivia quiz covers the red variety of corundum that has been prized for at least two thousand years and today includes both the most expensive coloured gemstone ever sold and the crystal at the heart of the first laser. The easy questions cover the colour, the birthstone month, the hardness and the mineral it shares with sapphire. From there the quiz moves into the science: the chromium that makes it red, the fluorescence that makes it glow, the rutile 'silk' inside every natural stone, star rubies, heat treatment and lead-glass filling. The hard end covers the Mogok Valley and Mong Hsu, Mozambique's Montepuez mine, the only rubies in mainland Europe, three-billion-year-old Greenland stones, the Verneuil process, Theodore Maiman's 1960 laser, the Black Prince's Ruby that is really a spinel, the Sunrise Ruby and the Estrela de Fura, Elizabeth Taylor's ring, the Rosser Reeves star ruby and the $32.5 million pair of slippers. Every answer was checked against encyclopaedia entries on ruby, the named stones, the ruby laser and the ruby slippers before publishing, and the supporting sentence is stored with each question. Our emerald and gemstone quizzes are natural next stops.
30 of 58 questions with answers and explanations. Play the quiz
Q 01Ruby is a red variety of which mineral?
Corundum
Corundum is so hard that emery, a dark grit rich in it, is glued to nail files and sandpaper to grind down almost anything softer.
Q 02Which element gives a ruby its red colour?
Chromium
Chromium is a two-faced colourist: a trace of it turns this gem red, yet the very same element is what paints emeralds green.
Q 03Ruby is the traditional birthstone for which month?
July
July has been ruby's month officially since 1912, when America's jewellers met and agreed a single modern birthstone list to tidy up centuries of competing traditions.
Q 04Ruby scores 9 and diamond 10 on which hardness scale?
Mohs
Mohs hardness is only a pecking order of what scratches what, drawn up by Friedrich Mohs in 1812, so its steps are uneven: diamond at 10 is about four times as hard as ruby at 9.
Q 05The word ruby traces back to a word for 'red' in which ancient language?
Latin
Latin: medieval writers called the gem rubinus lapis, 'red stone', and the same red root gives us rubric, a heading that scribes once wrote in red ink.
Q 06What name is given to the brightest, most valuable shade of ruby red?
Pigeon blood
Pigeon blood need not be a pure red: gem bodies allow the prized shade a slight purplish tint, and a stone that earns the name commands premium prices.
Q 07What is the chemical make-up of ruby?
Aluminium oxide
Aluminium oxide is colourless when pure, so a ruby owes all its colour to a trace impurity; the same compound forms the thin skin that stops aluminium foil and cans from corroding.
Q 08Which fabric lends its name to the fine, needle-like rutile inclusions found inside many natural rubies?
Silk
Silk sounds like a flaw, yet these fine needles can scatter light into facets that would otherwise look dark, so a little of it can make a ruby more beautiful, not less.
Q 09What optical effect do 'star rubies' display?
Asterism
Asterism comes from the Greek for star: light bouncing off aligned needle inclusions draws the rays, which only show if the cutter leaves a smooth dome instead of facets.
Q 10Which effect makes the finest rubies seem to glow from within in daylight?
Fluorescence
Fluorescence is triggered even by the ultraviolet in ordinary daylight, and the red light the gem gives off in response deepens its own colour.
Q 11In the United States, a stone too pale to meet the minimum colour saturation for ruby is sold as what?
Pink sapphire
Pink sapphire is a label barely a century old and still argued over: some gem-producing countries have always counted pink stones as rubies, while the markets that buy them split the two apart.
Q 12Which country's Mogok valley was for centuries the world's main source of rubies?
Myanmar
Myanmar, the former Burma, is where warriors are said to have pushed rubies under their skin in the belief that this made them invincible in battle.
Q 13Rubies found near Montepuez in 2009 turned which African country into a major new source of the gem?
Mozambique
Q 21Which crown holds the Black Prince's Ruby?
Imperial State Crown
The Imperial State Crown is the working crown: the monarch is crowned with St Edward's Crown, then swaps it for this one to leave the Abbey, the great red stone mounted just above the Cullinan II diamond.
Q 22What is the Sunrise Ruby named after?
A poem by Rumi
A poem by Rumi gave the gem its name: the 13th-century Persian mystic has sold millions of books in modern translation and is often described as the best-selling poet in the United States.
Q 23For how much did the Sunrise Ruby sell at auction in Switzerland in May 2015?
US$30 million
Mozambique had no known rubies near Montepuez until 2009, yet within a decade its mines ranked among the most prolific on Earth and their best stones were being compared with Asia's finest.
Q 14Ancient Sanskrit gave ruby a name that translates as what?
King of precious stones
King of precious stones: the name is ratnaraj, whose 'raj' is the royal word heard in maharaja, and ancient Hindus held that offering fine rubies to Krishna would see them reborn as emperors.
Q 15In 2017, a ruby mine opened near Aappaluttoq on which northern island?
Greenland
Greenland's mine kept every ruby in one company's hands from the rock face to the finished gem, a mine-to-market paper trail that is almost unheard of for coloured stones.
Q 16What is the most common treatment applied to rubies?
Heat
Heat is so routine that buyers assume almost every ruby has been cooked to deepen its colour and clear its haze, so a fine stone proven untouched is the rare exception and commands a large premium.
Q 17What material is used to fill fractures in low-grade rubies to make them fit for jewellery?
Lead glass
Lead glass seeps into the cracks and makes a cloudy stone look clear, but the trade values such rubies far below other stones, and the delicate filler needs gentle cleaning.
Q 18Traditional ruby-red 'cranberry' glass gets its colour from tiny particles of which precious metal?
Gold
Gold gives the glass its glowing red, a recipe lost for centuries and rediscovered by 17th-century alchemists, and the precious ingredient is why it has always been a luxury.
Q 19The Black Prince's Ruby, a famous stone in Britain's Crown Jewels, is actually what?
A spinel
A spinel: for centuries any big red gem was simply called a ruby, and only in the 18th century did chemists show that stones like this one were a different mineral altogether.
Q 20Which English king is said to have worn the Black Prince's Ruby at Agincourt in 1415?
Henry V
Henry V is said to have worn it set in his helmet at Agincourt, though the Royal Collection admits nobody can prove today's jewel is that same stone.
US$30 million made it the costliest coloured gemstone ever auctioned at the time, yet when the same ring came back to auction in Geneva in 2023 it fetched less than half that.
Q 24Estrela de Fura, a record-setting ruby, takes its name from the official language of its African homeland, which is what?
Portuguese
Portuguese for 'Star of Fura', after the firm that unearthed it in 2022: cutters ground away almost half of the 101-carat rough, and the finished gem sold for $34.8 million in 2023.
Q 25What happened to the giant carved Liberty Bell Ruby in 2011?
It was stolen in a heist
It was stolen in a heist: armed robbers tied up the staff of a Delaware jewellery store and smashed the cases with hammers, and none of the haul had been recovered when the gang was charged in 2014.
Q 26Whose 8.24-carat ruby ring broke the price-per-carat record in 2011?
Elizabeth Taylor
Christie's sold her whole jewellery collection that December, including a ruby necklace that also fetched millions.
Q 27In the King James Bible's Book of Proverbs, whose price is said to be 'far above rubies'?
A virtuous woman
A virtuous woman: the verse opens a 22-line acrostic in which each line starts with the next letter of the Hebrew alphabet, and many Jewish families sing it at the Friday-night Sabbath table.
Q 28Which comedian played the flamboyant media star Ruby Rhod in the 1997 film The Fifth Element?
Chris Tucker
Chris Tucker inherited the part from a pop star: Prince was first lined up to play Ruby Rhod, and Jean Paul Gaultier's costume sketches for him were later shown in a museum.
Q 29Dallas nightclub owner Jack Ruby is remembered for shooting which man in front of live television cameras?
Lee Harvey Oswald
Lee Harvey Oswald was being led through the basement of Dallas police headquarters for transfer to the county jail, two days after President Kennedy's assassination, when Ruby shot him.
Q 30In 1960, Theodore Maiman used a synthetic ruby rod to build the world's first working example of which device?
Laser
The laser: rivals had dismissed ruby as a material that would never work, but Maiman found errors in their sums, and his small rod fired the first beam on 16 May 1960.