A Gorgeously Gem-Studded Quiz

Answer:

Many materials have been used in jewelry or for other ornamental purposes since the beginnings of humankind. Most of them are minerals, though a few - such as coral, amber, pearl, and jet - have organic origin.

Jet is fossilized wood, characterized by its very dark brown or black colour, which becomes lustrous when polished. Used as a gemstone since antiquity, It became fashionable in the 19th century for mourning jewelry, often paired with elaborately cut steel.

Aventurine is a form of quartz, translucent or opaque with a shimmering appearance due to mica inclusions. Similar to the much more expensive jade, it is most commonly green, though other colours are also found. Carnelian, a form of chalcedony (like agate, onyx and jasper), is also part of the quartz group. With its distinctive red-orange colour (due to the presence of iron) and translucent appearance, it has been widely used since antiquity - in particular for engraving as cameos or signet rings.

Malachite is a copper mineral characterized by its intense green colour and unique swirling patterns. Being relatively soft, it is easy to carve, and has been extensively used throughout history as an ornamental stone as well as a gemstone. Chrysocolla is also a copper mineral, whose name means "gold glue" in Greek. With its stunning blue-green colour and relative abundance, chrysocolla has often been used in place of the less common (and thus more expensive) turquoise; in ancient times it was also used as a pigment for painting and cosmetics.

The birthstone for the month of August, peridot is a transparent variety of olivine that comes only in various shades of yellowish-green. It is a relatively hard, durable gemstone that has been employed in jewelry for thousands of years. In the past, specimens of particularly vivid green hue were often mistaken for emeralds.

The name tourmaline denotes a group of transparent gemstones that come in a wide range of colours - sometimes more than one in the same stone. They are often referred to with their own specific names (such as rubellite for the red-pink variety, and verdelite for the green one). Some colour varieties - such as blue-green tourmalines from Brazil - can command very high prices.

Larimar is a variety of the silicate mineral pectolite that is found in only one location in the Dominican Republic. It comes in a wide variety of shades of blue, from bluish-white to indigo through blue-green (hence its name, which contains the Spanish word for "sea"), with a silky luster. Usually cut into cabochons, larimar is sensitive to light and heat, and its colour may fade if it is directly exposed to either.

Often used as a substitute for the harder and more expensive sapphire, iolite owes its name to the Greek word for "violet". This stone (a transparent variety of cordierite) comes in various shades of blue, from an intense blue-violet to almost colourless. Its most distinctive feature, however, is its pleochroism - meaning it displays different colours according to the angle from which it is viewed.

Spinel is one of the most valuable gemstones listed here. It is a rare stone that comes mainly in shades of red and blue: because of that, in the past spinels were often confused with rubies and sapphires. Some famous red stones set in the Crown jewels of various countries (including the UK) are spinels, though for a long time they were referred to as "balas rubies".

The six wrong answers all belong to the plant kingdom: three are trees or shrubs (poplar, laurel and bergamot), and three are herbaceous flowering plants (chrysanthemum, columbine and rocket).