Gold is a
natural element and
is often found in pure form because it is stable and doens't easily react with
other chemicals to form other minerlas. It is metallic and opaque, most
often found as nuggets or grains rather than crystals (which do exist).
It is dense, sectile, soft and easily bent. It is golden-yellow in
colour but can be pale when alloyed with silver. It doesn not tarnish
and makes excellent jewellery.
Banded iron by Richard Droker via Flickr.com
Iron is most
often found in
alloy with nickel, and even then it is a rare element to find on the
Earth's surface. There seems to be mush more of it in the space because
meteorites often contain iron and nickel. It is also believed that it
is much more common in the earth's core. It is metallic and opaque,
black or grey in colour and very magnetic. It is often granular or
massive, although cubic crystals do exist.
Copper element by Paul via Flickr.com
is also a native
element, stable enough to not to react with other elements too much but
it is sometimes found in minerals such as copper oxides etc. It is
opaque, and pinkish when fresh, but tarnishes and turns into brown. It
is often massive in habit (although crystals do exist), and it is soft
and bends easily. It is often found in mafic and ultramafic igneous
Zinc mineral by Mike Beauregard via Flickr.com
Zinc is a
that is not found by itself but in minerals. Such minerals include but
are not limited to Sphalerite, Willemite, Clinohedrite, Zincite,
Smithsonite, Phosphophyllite, Fraipontite, Wurtzite, Staurolite,
Jeffersonite, Rosasite, Goslarite, Herbertsmithite, Reinerite, Adamite
Galena by Mike Beauregard via Flickr.com
Galena is a
more exactly a lead sulphide. It is a common ore mineral and often
found in lead-zinc-copper hydrothermal depositis. It is lead-grey in
colour and often forms crystals but can also be found as massive
habits. It is often associated with other minerals such as pyrite,
chalcopyrite, sphalerite, calcite, quartz and fluorite.
Sphalirite, Ian Geoffrey Stimpson via Flickr.com
is zinc sulphide. It
is not common on its own, but more often in alloy with iron. It is
greenish without iron, black with little iron, and reddish with much
iron. It has coarse crystals and is often massive, and it can form
stalactitic or botryoidal aggregates. It is mainly found in
hydrothermal lead-zinc depositis and it is a main zinc ore.
Sulphur by Peter Nijenhuis via Flickr.com
Sulphur is a
natural element which is yellow and can either be massive, or occur in
tabular or pyramidal crystals. It most often forms around volcanic
craters and hot springs, but can also occur in some sedimentary rocks,
or be the result of the breakdown of sulphide ore deposits.
fool's gold, is a common mineral in all types of rocks.
It is metallic, opaque and while most known for its cubic crystals, can
also have pyritohedral or octahedral crystals, or be granular, massive,
reniform or potryoidal in habit. It is pale silvery-yellow when fresh
but gets darker as it tarnishes.
is deeper yellow than pyrite, but it is also metallic, opaque, and can
occur in massive, botryoidal, reniform or compact habits. It is often
found in hydrothermal sulphide deposits, where it has formed in
hydrothermal veins. It is an important copper ore.
Azurite is a
deep azure blue copper hydroxide. It can be earthy, nodular or massive,
or it can form prismatic crystals. It is found in the oxidised zones of
copper deposits, which have formed in limestone and other carbonate
rocks. Like other carbonates, it reacts to HCl.
a pale to dark green common secondary copper mineral. It can be
botryoidal or stalactitic, or form prismatic, circular or twinned
crystals. It can be transculent to opaque, and it is formed in the
oxidised parts of copper deposits, often together with azurite.
Malachite has been used extensively in jewelry, and even to decorate
an iron oxide which can be very various in appearance. Specular
hematite for example comes in a hexagonal, platy, shiny,
silver-coloured crystal. Massive hematite is reddish brown and has a
massive, earthy habit. Kidney ore is red and reniform. Hematite is
found in hydrothermal veins, contact metamorphic rocks, volcanic
fumeroles, and ironstones.
common carbonate mineral, is either transculent or transpalent, and can
come in many colours such as colourless, white, red, grey, green,
brown, or black. It can be massive, fibrous, granular or stalactitic,
or form prismatic, rhombohedral or scalenohedral crystals.
It is the main mineral in limestones and marbles.
List of minerals - Beryl
Mineral beryl by Orbital Joe via Flickr.com
Beryl is a
silicate mineral, which can either be massive and in other earthy
habits, or form beautiful crystals that, depending on their colour,
have a name amongst gemstones.
It can be red, white, colourless, green (emerald), blue (aquamarine), yellow (heliodor), and pink (morganite). It forms mostly in igneous rocks related to
granites, but can also be found in schist.
List of minerals - Clay
Clays by Miguel Vera León via Flickr.com
are very fine grained minerals such as kaolinite, illite, halloysite,
bentonite, and green and brown nontronite. Under the microscope it can
be seen that they consist of thin plates. They form mostly from the
weathering of feldspars and other minerals rich in aluminium. They are
often found in soils, sediments, and sedimentary rocks.
an iron and magnesium rich silicate mineral (like many other minerals,
it is actually a solid solution, i. e. a group of minerals which vary
in compositions between the iron-rich end member fayalite and the
magnesium rich end member fosterite. They are most often green, but can
also be brown, grey, white or yellow. It is found in mafic rocks.
also a group of minerals such as grossular, almandine, spessartine and
pyrope garnet. Spessartine is greenish, while the others are reddish in
colour. They all have cubic crystals (pyrope's are rounded cubics),
while grossular is transculent and the others are opaque.
Almadine is the one that occurs in garnet schist.
an aluminium oxide mineral, which, just like beryl, forms crystals that
are known amongst gemstones, such as ruby
(red), padparadscha (pink),
and white, blue, orange, violet, green and yellow sapphire. But it can
also be granular or massive, or mixed with magnetite (emery). Corundum is
found in pegmatites, syenites, and gneiss.
forms crystals known as gemstones,
however they are all called zircons. They can be red, yellow, brown,
green, grey or colourless. Zircon can form irregular grains,
fibrous aggregates or prismatic crystals. It can be transparent or
opaque. Zircon can contain traces of uranium and be slightly