Aventurine is a very tactile gem stone, and it is a translucent to opaque variety of microcrystalline quartz. It contains small, but advantageous inclusions of shiny minerals which give the stone an effect which is know as aventurescence. It comes in a variety of colours ranging from the more common green, a creamy green, to peach, brown, and even blue. It is not only used for making jewellery, but also for ornamental purposes such as vases, bowls and figurines. Aventurine is found in many places, such as, Brazil, India, Chile, Spain, Russia, Austria, and Tanzania. It is often mistaken for Amazonite or Jade, and it is 6.5 on the Mohs scale of hardness.

The Mohs scale of hardness was devised by a German mineralogist called Frederich Mohs (1773-1839) in 1812. He selected the ten most commonly readily available minerals to show the difference in hardness of each. The scale runs from 1-10, 1 being the softest, and 10 being the hardest.

THE MOHS SCALE

Talc = 1
Gypsum = 2
Calcite = 3
Fluorite = 4
Apatite = 5
Orthoclase = 6
Quartz = 7
Topaz = 8
Corundum = 9,

and this includes sapphire and ruby, and they are twice as hard as topaz, even though it is only one number more on the Mohs scale of hardness.

Diamond = 10

thereby being the hardest mineral mined. It is four times harder than corundum, even though it is only one number more on the Mohs scale of hardness.