Q 01/05

Which purple stone, its Greek name meaning 'not drunk', was a 'cardinal' gem until Brazilian finds made it common?

A) Amethyst

B) Lepidolite

C) Sugilite

D) Charoite

Answer · why

A) Amethyst

Amethyst sat with diamond and the big coloured stones as one of five cardinal gems until the 18th century, when Brazil's huge deposits made it cheap. ...

Q 02/05

Which blue-violet gem, found in 1967 in the Mererani Hills, did Tiffany & Co. rename and launch in 1968?

A) Labradorite

B) Apatite

C) Tanzanite

D) Kyanite

Answer · why

C) Tanzanite

Tanzanite is the name Tiffany & Co. gave blue-violet zoisite in 1968, judging the mineral's real name too unappealing to sell. The whole supply comes ...

Q 03/05

Which aluminium-oxide mineral goes by one gem name when red and another in every other colour?

A) Tourmaline

B) Corundum

C) Spinel

D) Zoisite

Answer · why

B) Corundum

Corundum gives the world two of the four precious stones: its chromium-red crystals and the sapphires of every other colour, blue included. The name c...

Q 04/05

Which word comes from 'elektron', the Greek for amber, because the rubbed resin takes a static charge?

A) Magnetism

B) Galvanism

C) Electricity

D) Voltage

Answer · why

C) Electricity

Electricity, electric and their relatives all descend from elektron, the Greek for amber, which bears a static charge when rubbed. Persian called the ...

Q 05/05

Which gem, classed as a mineraloid because it has no crystal structure, did NASA announce in 2008 it had found on Mars?

A) Jasper

B) Opal

C) Agate

D) Onyx

Answer · why

B) Opal

Opal deposits on Mars were announced by NASA in late 2008, the same year a big new opal field turned up near Wegeltena in Ethiopia. Opal is hydrated s...