And Allied Minerals
Looking for Stones Suppliers?
Let us help you find the right suppliers!
Free, Easy, Simple way to find Suppliers.
Of the several zirconium minerals known only two, viz., zircon and
baddeleyite are of commercial importance.
During the Middle Ages, zircon was believed to contain remedial
power, protecting the wearer from diseases and banishing insomnia. The
name "zircon" is believed to have derived from the Arabic
words, "zar", meaning gold, and "gun", meaning
color. It was discovered in Germany in 1789 by Martin Klaproth.
The Present Scenario
Thailand and Cambodia are the world's major suppliers of zircon with
large deposits near the border of the two countries. Vietnam, Burma,
Sri Lanka and Africa also provide a large supply of these marvelous
gemstones to the world market.
is the chief mineral of zirconium, a versatile metal. The zircon is a
common accessory mineral of igneous rocks, like syenite, granite and
diorite. Economic deposits are, however, concentrated along the beach
sands and found in association with ilmenite, rutile etc. as it occurs
in the beach sands of Australia, USA, South Africa, West Africa and
Zircon invariably contains hafnium. There are fourteen zirconium
minerals of some importance and all of them contain hafnium. It has
been observed that the hafnium content in the minerals originating
from syenite rock is less than in those occuring in granite.
......67.2% SiO2 ......32.8%
||Brown Red Yellow
Green Blue Black colorless
fluorescent and darker crystals may be radioactive due to impurities
of rare earth elements.
hardness, luster and density
Zircon is the birthstone of the month of December.
piping in corrosive environments
Zircon, a naturally occurring gemstone, has colorless, yellow,
orange, red, blue, brown and green varieties. Zircon, by it's name, is
sometimes confused with cubic zirconia ("CZ"), which is
synthetic. In addition, both have been used as diamond substitutes.
Zircon has a high refractive index which is responsible for it's
diamond like appearance. Zircon can be distinguished from diamond by
it's double refraction and by wear and tear of it's edges, as compared
to diamond which is very much harder.
Green and brown colors of zircon are not enhanced. Yellow zircon is
rarely heat treated to improve color. Blue, red and colorless are
always heat treated brownish crystals to produce these colors.
Zircon, baddeleyite or manufactured zirconia are all useful
refractory materials. They are valued for the preparation of special
moulds and refractory bricks. High-grade zircon melts at about 2190ºC,
softens between 1600ºC and 1800ºC and shows little shrinkage
upto 1750ºC. Zircon exhibits many characteristics that make it
very suitable for super refractory purposes. In addition to a high
melting point it was very low thermal expansion and good resistance to
abrasion. Zircon is used when acidic refractory is required while
zirconia refractories are considered to be basic. A cheaper type of
zircon-refractory is prepared with mixing zircon with alumina. It is
reported to have refractory properties as good as those of zircon. At
high temperatures the following reaction takes place:
The dissociation of zircon starts at 1400ºC and at about 1600ºC
a complete reaction takes place forming a stable product of zirconia
and mullite. The high grade zircon sand is largely used in foundry as
mould. It does not wet the molten metal, thus giving a better and
smoother surface to the casting. It is estimated that about 75% of the
total world zircon production is used as moulding sand and in the
manufacture of refractory bricks, zirconium compounds and ceramics.
Only 25% is used for the extraction of metal or in the manufacture of
Prepared zirconia and also zircon are extensively used in the glass
and ceramic industry for opacifying enamels, porcelain and glazes.
Zircon sands bonded into bricks are also used in large quantities as
refractory bricks in glass and aluminium industries. Zircon has
special properties of resistance to spalling and wetting by glass and
aluminium which makes it suitable for the above purpose. Finely
powdered zircon and zirconia are used as an abrasive in polishing
This country is the leading producer and exporter of zircon which is
obtained as byproduct of rutile recovery from the beach-sands. The
largest concentration of such sands is found on the eastern coast,
extending over 160 km, in Queensland. Concentration of such sands is
observed in the Byoon Bay, New Brighton-Cudgera, Cudgen and
Currimbin-Southport area and on North Stradbroke island. It is
reported that on this island the heavy sands contain about 25% zircon.
Deposits are worked by several companies. Australian deposits are
wide-spread and quite large.
The source of zircon in this country is Florida beach and Trail
ridge. Production in Florida started in 1922 from the Pablo Beach area
near Pdonta Vedra. The total heavy minerals in the beach of this area
contain hardly 4 to 4.5%. The heavy mineral concentrates give 45%
ilmenite, 14% zircon besides other minerals. Another area near Starke,
Florida, was opened up in 1948.
One of the most important sources of zircon, rutile and ilmenite
discovered in the USA lies in Trail ridge some 72 km inland formed in
mid-Pleistocene time as a sands pit part of an ancient beach. It
consists of a strip of ridge running for a distance of 40 km, ranging
from 900 metres to 2400 metres in width with an average height of 45
metres. The average concentration of heavy minerals is about 3.9%. the
percentage of zircon in the concentrate is 14%. The estimated reserves
of heavy sands in this deposit are 21 million tons and the potential
reserves of zircon are estimated at 2.5 million tons with 80%
recovery. Production statistics of zircon in the USA are kept secret.
The zircon minerals, like baddeleyite, orvillite (altered zircon) and
zirkite, are mined from open pits in the Pocos de Caldas plateau in
The beach-sand between Rufisque and the mouth of the Saloum river is
reported to contain zircon.
Republic of South Africa
The beach-sands of Durban contain zircon which is mined. The reserves
The known source of zirconium mineral is eudialyte, which is
recovered from the apatite deposits in the Kola peninsula.
The beach-sands at Pulmoddai and Tirukkovil in eastern Ceylon contain
about 25% of zircon.
An appreciable quantity of zircon is present in the alluvial tin
deposits. It is reported that the Japanese produced 741 tons of zircon
during the occupation.
The beach-sands of Kerala and adjoining Madras coasts contain an
average 5 to 10% zircon. It is recovered from the tailings of ilmenite
plants. The production of zircon in the country is controlled by the
Atomic Energy Department, Government of India.
Still Searching for Suppliers?
Let us help you find the right suppliers!
and receive quotes from genuine suppliers!