There are over 4000 different minerals.
Some of them are instantly recognisable, but many can look very similar. So how do you tell them apart?
There are a few tests that you can do to find out a minerals identity.
Minerals with distinctive colours
Some minerals exhibit particular colours that make them easier to recognise.
|Yellows and golds examples||Reds and oranges examples||
Purples and blues
Gold: gold, pyrite, chalcopyrite
Yellow: sulphur, carnotite
Rose red: rhodonite
Red wine: cuprite
Ruby red: ruby
Blue: azurite, lazulite
Sky blue: sapphire
Opaque green: malachite, varsicite
Jade green: jageite, nephrite
Clear green: emerald, olivine
Mohs Scale of Hardness
The Mohs scale of hardness was created by Friedrich Mohs a German mineralogist in 1812. When mineralogists talk about hardness, they mean scratch hardness- the minerals resistance to being scratched.
The Mohs scale arranges minerals from 1 to 10. 1 is Talc and 10 is Diamond. Diamond is the world’s hardest mineral. In the original Mohs Scale, ten minerals were arranged in order of increasing hardness and were assigned the numbers one to ten. These ten minerals are shown here:
|Mohs mineral||Mohs Number||Can be scratched by||Simple Classification|
|Apatite||5||Knife blade or glass||medium|
|Corundum (emery)||9||Knife sharpener||hard|
Glow in the Dark
Some minerals glow in the dark! The minerals appear to glow when these different types of light are shone onto them. This glowing effect is called fluorescence. The word fluorescence is taken from the mineral fluorite, which usually glows a bright purple/blue under UV light.