10 most difficult gemstones riddlesMinerals quiz
What was used as a unit of mass in the classical times?
a drop of lead
handful of sand
Carat, a unit of mass equal to 200 mg, is derived from a carob seed (Greek kerátion). People commonly believed that the seeds have unusually low variability in mass. Modern research denied this claim.
Where are emeralds found the most?
in South Africa
Colombia is by far the world's largest producer of emeralds, constituting 50–95% of the world production. The Colombian emeralds are also the purest. The emerald trade is at the center of funding of ongoing civil conflict in Colombia, second to drug trade.
What's the origin of the word "turquoise"?
Turku City in Finland
Turkey as a country
Turkusy, fake region
The name Turquoise was established in the seventeenth century and came from the name of Turkey (turquoise is French for "Turkish"), because the mineral was first brought to Europe from Turkey. Ancient Romans called this rock Kalalit.
What is the Greek name for amber?
Words like "electricity" come directly from the name of amber. Already the ancient Greeks noticed that this stone has a certain mysterious property: when rubbed with fur, it begins to attract particles of dust...
Where do you have the best chance to find a natural diamond?
near the volcano
in the coal mine
in the silver mine
at the beach
It is sometimes mistakenly believed that diamonds are made from coals. High pressure and heat is required for the formation of diamonds from carbons, but these carbons are not the ones that form coal. Diamonds are formed deep under the surface and are brought up during outbreaks of volcanoes.
What gemstone is this?
Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3(OH)2. This opaque, green banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and spaces, deep underground.