study of zircon

1. The University of Azad Jammu & Kashmir
The Institute of Geology
TOPIC
STUDY OF ZIRCON
GROUP # 04
SUBMITTED BY
SYED RASIB ALI
ROLL # 26
SUBMITTED TO
SIR SHAHAB PERVAIZ

2. OUTLINE:.
 Introduction
 Physical properties
 Optical properties
 Varieties
 Occurrence
 Zircon sources
 Uses
 similar gemstone
 gems market in pak
 Mining in pak
 Gallery
 References

3. Zircon:.
Zircon is a mineral belonging to the group of Silicates, Nesosilicates. Its
chemical name is zirconium silicate and its corresponding chemical formula is
ZrSiO4. While zircon in fashioned form can be found in a wide range of colours the
crystals are usually reddish brown and heat treatment is needed to produce the
colourless, golden yellow and bright blue colours most seen in jewellery. Other
colours, often very pleasing, might be called fancy zircons as the range is
considerable. . Other colours, often very pleasing, might be called fancy zircons as
the range is considerable. We should understand from the first that some zircons are
much older than others and, like older people.
Properties of zircon:.
Cleavage: Indistinct
Color: Brown, Reddish brown, Colorless, Gray, Green.
Density: 4.6 - 4.7, Average = 4.65
Fracture: Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.
Luster: Adamantine
Streak: white
Hardness: 7.5 – Garnet
System: Tetragonal
Tenacity: Brittle
Transparency Transparent to opaque
Specific Gravity 4.6 - 4.8
Optical Data of Zircon:.
Type: Uniaxial (+)
Surface Relief: Very High
Dispersion: Very strong
Pleochroism: Weak

4. Varieties 0f Zircon:.
Jacinth:
Yellow, orange, brown, or red variety of Zircon. Also synonymous with
Hyacinth. Though the terms Jacinth and Hyacinth are no longer used in the gem
trade, they are historically important names going back to biblical times. In
ancient times, before there were mineralogical classifications for gemstones, the
term Hyacinth may also have referred to an orange or brownish Topaz.
Jargon:
Colorless, pale gray, or pale yellow variety of Zircon.
Matura Diamond:
Trade name for colorless Zircon.
Starlite:
Blue gem variety of Zircon. The color of Starlite is rarely natural, and is almost
always heat treated.
Occurrence:.
Zircon, zirconium orthosilicate, is found in most igneous rocks and some
metamorphic rocks as small crystals or grains, mostly widely distributed and
rarely more than 1% of the total mass of the rock. It is also found as alluvial grains
in some sedimentary rocks due to its high hardness. Zircon has a high refraction
index and, when the crystals are large enough, is often used as a gemstone.
In geology, zircon is used for radiometric dating of zircon-bearing rocks (using
isotopes of U which is often present as an impurity element, as is Th, radiogenic
Pb, Hf, Y, P, and others).
 Zircon is a common accessory to trace mineral constituent of most granite
and felsic igneous rocks.
 Zircon is rare within mafic rocks and very rare within ultramafic rocks

5.  Due to its hardness, durability and chemical inertness, zircon persists in
sedimentary deposits and is a common constituent of most sands.
Zircon Sources:.
Zircon sources include Cambodia, Burma (Myanmar), Sri Lanka
(Ceylon), Australia, Tanzania, Mozambique, Madagascar, Nigeria, Pakistan, and
Afghanistan.
Uses:.
Zircon is an important gemstone, with several color forms used in various
forms of jewelry. Zircon is also the most significant ore of the element zirconium,
and it is also the most important ore of the rare element hafnium, which can be
present in considerable quantities in Zircon. In several localities, Zircon is also an
ore of the radioactive element thorium.
Zircon of all colors are used as gems, but blue, golden-brown, and white are
the colors most often used. Blue Zircon, the most popular color, has a lively pastel
blue, and occasionally has a very desirable striking bright blue color. Colorless
Zircon is usually cut with a brilliant cut to bring out its fire to its fullest capability.
It is often used as a cheaper, yet natural alternative to Diamond. The other color
forms (yellow, green, pink, and purple) are less often seen in jewelry.
Zircon is the traditional birthstone for December.
Production chart of worldwide of zircon.

6. Similargemstones:.
Because Zircon occurs in so many colors, there are many gemstones that
resemble it.
Colorless Zircon resembles Diamond. It also resembles synthetic Diamond
simulants such as Cubic Zirconia and Strontium Titanate. It is distinguished from
these and other colorless gem forms by its strong double refraction.
Blue Zircon can be similar to Aquamarine, Blue Topaz, Blue Tourmaline,
and Blue Spinel; Golden-brown Zircon can be similar to Topaz, Citrine, and
Sapphire; Yellow zircon can be similar to Yellow Diamond, Yellow Sapphire,
Golden Beryl, Chrysoberyl, and Topaz; and Pink Zircon can be similar to Rose
Quartz, Morganite, Kunzite, Spinel, and Pink Topaz.
The luster, fire, and double refraction make Zircon gemstones
distinguishable from most others.
Gem markets:.
The southern port city of Karachi was once the biggest market of facet and
rough cut gems in Pakistan. However, after the Soviet invasion of Afghanistan, the
significance of Karachi was reduced and Peshawar became the hub of gemstones
trade. Due to the long and porous border with Afghanistan, many gemstones from
the country are now also found in Pakistan and since 1979, Peshawar is the only
direct market for all gems found both in Pakistan and Afghanistan.
Pakistan Gems and Jewellery Development Company regularly holds Gem
Bazaars (exhibitions) in Quetta and Peshawar where gemstones attested by
Gemstone Identification Laboratory are traded. In Islamabad, so far three such
exhibitions have been held. In January 2012 exhibition, around two hundred
companies from Pakistan displayed their items. The third Islamabad Gem
Exhibition was held in February 2013 where 80 national gem traders displayed
their products.
Mining areas in Pak of Zircon:.
Pakistan has large reserves of mineral ores and gemstones. Pakistani
gemstones include a variety of minerals such as peridot, ruby, aquamarine, topaz,
ruby and emerald, making the country significant in the mineral world.

7. In Gilgit Baltistan mining area is Chillas.
Baluchistan mining area is chagai.
Also the Sindh and tribal areas of Pak zircon is reported
Gallery:.