Guide about semi precious stones

Guide about semi precious stones
As we be familiar with, the human being, from its existence, has always felt devotion
and endowed with a certain mysticism to precious or strange stones or stones very
difficult to find in nature, conferring different uses: for ornamentation, as a symbol of
power and exclusivity, associated with the cult of certain deities and even using them
to heal or otherwise.
Precious stones and semi precious stones are, almost in their majority, minerals;
some of them, however, are organic.
Precious stones
To distinguish between precious stones and semiprecious stones, three factors are
Its beauty and perfection. When we talk about the beauty and perfection of a
stone, whether precious or semiprecious, we refer to its colour, brightness,
transparency and purity. A pure gemstone, without imperfections and with a radiant
colour, can have an even higher value than a diamond with similar characteristics.
The only three stones or gems considered precious-in addition to diamond-for the
above factors is ruby, emerald, white sapphire and blue sapphire.
To take into account that only between 1% and 5% of the rubies extracted from nature
are selected for use in jewellery.
His name comes from Persian; its meaning is "green stone".
The emerald stones for sale have always been highly valued, since, despite the
existence of other green stones, the only crystal was emerald. At present, we know
other crystalline stones of green colour, but none of them is comparable in colour and
transparency to the emerald.
Only thirty percent of the high quality cubic zirconia mined in the mines is carved
for commercialization in jewellery, and of these only in two percent of them there are
no visible inclusions. Hence, its rarity and high market value.
Like the ruby, it belongs to the Corindon family. Its distinctive feature is its intense
blue colour; although there are sapphires of other shades, the most valued and
appreciated is the blue sapphire. Any Corundum of a colour other than red is called
sapphire; hence, it is adjective and it is called blue sapphire. Natural aquamarine is
also good example of the precious gems.
Like the ruby, blue sapphire has a hardness of 9 on the Mohs scale. Its rarity increases
daily, since many of the sapphire deposits are currently depleted, and those that are
discovered cannot meet the demand.
An important aspect to take into account is the treatments that are made to natural
gems. The most usual treatments are: heating, dyeing and filling of fissures. These
treatments improve the optical properties and are admitted. It is important that this is
specified and mentioned since in some cases the value of a gem changes substantially
when treated.
Another fundamental concept is the existence of inclusions. Natural gems like
synthetic opal have cavities that house inclusions that can be other minerals, liquids
or gases.
However we must be careful to make differences between some synthetic stones that
are really transformations in laboratories but that result with such perfect
characteristics that are considered genuine gems and not a simple artificial stone, to
give it a name.