is an organic gemstone which has been fossilised from ancient plant
material. It is transparent or transculent, and soft enough to be used
in making jewelry. It often has insects or other small animals trapped
inside. It is found in many different places in the world, but some of
the largest deposits are found around the Baltic Sea in northern Europe.
Alexandrite by the justified sinner via Flickr.com
are known for their colour changing properties. Their colour can change
from emerald blue to purple, red and bluish green depending on the time
of the day. They got their name from the Russian Czar Alexander II,
whose birthday it happened to be when the gem was first found in Ural
Mountains. The gem is found in some pegmatites, schists, marbles and
Beryl stone by Orbital Joe via Flickr.com
is a mineral that forms prismatic crystals and can come in different
colours such as green (emerald), sky blue to bluish-green (aquamarine),
colourless, golden to greenish yellow (heliodor), brown, reddish-brown,
pink (morganite) and red. It is one of the most variable ones on this
list of gemstones.
Emerald stone by Cliff via Flickr.com
Emerald is a
beautiful green gemstone which is a variety of
beryl. The crystal is prismatic and can grow very large. It has been a
very popular gem since ancient times and is still today one of the most
precious gemstones. It is mostly found in granitic rocks and pegmatites, but can also be
found in some metamorphics such as schists.
is a gemstone that forms beautiful cubic crystals. There are different
types of garnet, such as almandine, spessartine, grossular and pyrope
garnet. They can be brown, red, orange, yellow, green, blue, purple,
pink, grey and black. Garnets are found in some igneous and metamorphic
Jade gems by Maia C via Flickr.com
is a gemstone often used in jewellery. It is most often green but can
also have other colours. The habit is most often massive but it can
also form crystals. It is found in mafic igneous rocks and some
metamorphic rocks. It is one of the gems on this list of gemstones that
you often see sold as jewellery on markets.
Moonstone. By the_justified_sinner via Flickr.com
most often bluish but can come in other colours. It is a
gem variety known as adularia, which forms from the silicate mineral,
potassium feldspar orthoclase. It is often found in silica-rich igneous
rocks such as granites and syenites, but also in pegmatites, and some sedimentary and
high-grade metamorphic rocks.
Opal is a beautiful
gemstone that does not form crystals and is therefore classified a
mineraloid and not a mineral. Ninety percent of the world’s opal is
found in Australia. It forms from silica-rich waters in low
temperatures - its chemical formula is quartz + water (SiO2 . nH2O). It
is one of the prettiest ones on this list of gemstones.
is a green gemstone of the mineral olivine. It forms thick tabular
crystals the colour of which can vary between yellowish green and
brownish green. It forms in mafic and ultramafic igneous rocks such as
basalts and similar. It is found in Europe, Middle East, south east
Asia, Australia, northern Africa, and north, central and south America.
Ruby stone by the justified sinner via Flickr.com
is a variety of the mineral corundum. It gets its colour from trace
chromium. It is an aluminium oxide and it forms hexagonal crystals. It
forms in igneous rocks such as syenites and some pegmatites, and also
in some high grade metamorphic rocks. It is a very highly valued
Sapphires by the justified sinner via Flickr.com
Sapphires are some of the most valued gems in the world and on this list of gemstones. Like ruby,
they are a form of the mineral corundum. They are most often blue, but
can also come in other colours such as green, yellow and transparent.
Like ruby, sapphires are found in syenites, some pegmatites, and some
high-grade metamorphic rocks.
By Catherinette Rings
Steampunk via Flickr.com
Tanzanite belongs to the
the mineral zoisite family. It grows prismatic crystals. It is
often blueish or purple but shows shades
of different colours when viewed from different angles. It is often
found in medium-grade metamorphic rocks such as schists and gneisses but can also
form in eclogites and amphibolites that have formed from calcium rich sedimentary rocks.
Topaz. By the_justified_sinner via Flickr.com
Topaz is a
mineral that forms prismatic crystals that can grow very
large. It is most often colourless or light blue, but can also be
yellow, red, pink, brown or orangeish-brown. It is most often found in
igenous rocks such as granites
and rhyolites, but
also in pegmatites and some high grade metamorphic rocks.
is the most common mineral on this list of gemstones, and it can come
in many different shapes and colours. It can be massive or form
crystals. Amethyst is purple quartz. Rose quartz is pink. Citrine is
yellow. Smoky quartz is dark to mid-brown. Milky quartz is white and
the transparent crystals are called rock crystals.
is a gemstone family - a very fine grained form of quartz. There are
many different varieties of it, such as moss agate, lace agate, fire
agate and banded agates. It can be red, blue, orange, yellow, green and
other colours. It is often banded. Here is more information on Agate