Tiffany & Co. Anniversary morganite and diamond necklace with a 175-carat cushion morganite.

1. A gem was named after JP Morgan

The American financier was a passionate gemstone collector, and Tiffany & Co’s biggest customer and patron in gemstone discovery. In 1910, a rare form of pink beryl was discovered in Pala, California, by Tiffany’s eminent gemmologist George Frederick Kunz, and thereafter the gemstone was named morganite in the banker’s honour. Altogether, JP Morgan had acquired three incredible collections of gemstones that numbered nearly 20,000 specimens.

2. Black diamonds aren’t actually black

Black diamonds appear black due to microscopic black or grey inclusions of other materials such as graphite, sulphite, other impurities or fractures.

Tiffany & Co. Chrysanthemum conch pearl and diamond brooch.

3. Pearls don’t just come from cultured oysters and mussels

While wild pearls are extremely rare, such natural pearls do not just come from saltwater oysters and freshwater mussels. Some mollusks that spontaneously produce pearls are the conch (pronounced konk); melo melo sea snail; lion’s paw scallop; abalone; venus mercenaria clam common along the US North Atlantic coast (the pearls are called quahog pearls); giant clam; and nautilus.

Tiffany & Co. Angelfish cuff with diamonds, blue chalcedony, spessartite garnets, blue and green sapphires, and onyx.

4. Chalcedony is the perfect gemstone for seal-making

Chalcedony is commonly used for making seals, not only because of its availability, affordability and hardness (6 to 7 on the Mohs scale), but because wax does not stick to it.

5. Amber can float in seawater

Amber is one gemstone you don’t have to be afraid of jumping into the sea with—it is denser than fresh water but less dense than salt water, and so it remains buoyant in the sea. Its exceptional lightness makes it hard to imitate, and there’s always an easy salt-water test to check its authenticity.

Simone Jewels Wave of the Orient multi-finger ring with a red garnet, diamonds, sapphires and Akoya pearls, Simone Jewels Oriental Pleats transformable necklace with a red garnet, diamonds and Akoya pearls.

6. The Garnet is named after a fruit

The Garnet’s name was historically derived from the pomegranate’s Latin name “granatum” because the most common red garnet bears the same juicy red hue of the fruit’s seeds.

Chopard Fleurs d’Opales ring with a nine-carat black opal, Cartier Étourdissant Lagon bracelet with an 85.42-carat cabochon-cut black opal as centre stone.

7. The Opal is the most colourful gem on earth

Beloved in the world of high jewellery and also a much-revered gemstone to the Chinese, the opal is the most colourful of all gemstones. It possesses the stunning ability to flash rainbow colours and iridescence, called play of colour, when the viewing angle is changed. The finest specimens, usually from Australia, can be worth more than diamonds. In fact, one of the most expensive opals on record is the 72-carat Virgin Rainbow, which shimmers and glows in the dark.

Van Cleef & Arpels Red Sea Vagues white coral and diamond earrings.

8. Precious corals aren’t just red or pink

The popular red or pink coral varieties are easily recognisable, but the organic gemstone also comes in gem-quality white, black, gold, white suffused with pink (called angel skin), and even blue. Black coral is the state gem of Hawaii, which also used to harvest the very rarest of all corals, the deep-sea gold coral, until it was discontinued due to strict regulations.

9. Fossils can be gemstones, too

Amber and jet are two commonly known gemstones that are actually ancient fossils. The former is fossilised resin secreted by prehistoric plants, while the latter is fossilised bituminous coal formed from dead trees. The more uncommon ones include ammonite (an extinct group of marine invertebrates), petrified wood (ancient wood that had been replaced with silica, opal or other mineral material), petrified palm (a fossilised fibrous material), peanut wood (a type of fossilised driftwood), and even gem bones (these are often dinosaur bones that had been in-filled and replaced by quartz and other minerals).

For more lesser-known facts, pick up a copy of Singapore Tatler Jewels & Time, out on newsstands now.