|A collection of uncut gemstones.|
In our modern world these are the stones that are considered precious diamond, ruby, sapphire and emerald. Some experts include the natural pearl on this list. The list of precious stones is not particularly scientific it rather tells of the rarity of these stones during ancient times. There are many stones that have as high a value as the so-called precious stones that are only considered to be semi precious. An outstanding example of this is the Alexanderite a variety of crysoberyl the changes from red to green tea pending on the type of light it is exposed too.
|A faceted blue tourmaline|
The words precious or semi precious used in the context of commercial gemstones is often misleading because it implies certain gemstones are intrinsically more valuable than others when it is just not true.