ZIRCON(HONEY)[GEM]

VARIETIES

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.



Listing description
Zircon (including hyacinth or yellow zircon) is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO4. A common empirical formula showing some of the range of substitution in zircon is (Zr1–y, REEy)(SiO4)1–x(OH)4x–y. Zircon forms in silicate melts with concentrated incompatible elements and accepts high field strength elements into its structure. For example, hafnium is almost always present in quantities ranging from 1 to 4%. The crystal structure of zircon is tetragonal crystal system
Detailed descrtion
Zircon (including hyacinth or yellow zircon) is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO4. A common empirical formula showing some of the range of substitution in zircon is (Zr1–y, REEy)(SiO4)1–x(OH)4x–y. Zircon forms in silicate melts with concentrated incompatible elements and accepts high field strength elements into its structure. For example, hafnium is almost always present in quantities ranging from 1 to 4%. The crystal structure of zircon is tetragonal crystal system. The natural color of zircon varies between colorless, yellow-golden, red, brown, blue, and green. Colorless specimens that show gem quality are a popular substitute for diamond; these specimens are also known as "Matura diamond".
The name either derives from the Syriac word ܙܐܪܓܥܢܥ zargono,[5] from the Arabic word zarqun (زرقون), meaning vermilion, or from the Persian zargun (زرگون), meaning golden-colored.[6] These words are corrupted into "jargoon", a term applied to light-colored zircons. The English word "Zircon" is derived from "Zirkon," which is the German adaptation of these words.[7] Yellow zircon is called "hyacinth", from the flower hyacinthus, whose name is of Ancient Greek origin; in the Middle Ages all yellow stones of East Indian origin were called hyacinth, but today this term is restricted to the yellow zircons.
Properties
Zircon is a remarkable mineral, if only for its almost ubiquitous presence in the crust of Earth. It occurs in igneous rocks (as primary crystallization products), in metamorphic rocks and in sedimentary rocks (as detrital grains). Large zircon crystals are seldom abundant. Their average size, e.g. in granite rocks, is about 0.1–0.3 mm, but they can also grow to sizes of several centimeters (a few inches), especially in pegmatites.
Owing to their uranium and thorium content, some zircons may undergo metamictization. The processes, related to internal radiation damage, partially disrupt the crystal structure and partly explain the highly-variable properties of zircon. As zircon becomes more and more modified by internal radiation damage, the density decreases, the crystal structure is compromised, and the color changes.
Zircon is a common accessory mineral that occurs worldwide. Noted occurrences include: Australia; Russia (Ural Mountains); Trentino, Monte Somma, and Vesuvius, Italy; Arendal, Norway; Sri Lanka; India; Indonesia, Java, Kalimantan, Sulawesi; Thailand; Ratanakiri, Cambodia; the Kimberley mines, Republic of South Africa; Madagascar; Renfrew County, Ontario, and Grenville, Quebec, Canada; and Litchfield, Maine; Chesterfield, Massachusetts; Essex, Orange, and St. Lawrence counties, New York; Henderson County, North Carolina; the Pikes Peak district of Colorado; and Llano County, Texas in the United States. Australia leads the world in zircon mining, producing 37% of the world total and accounting for 40% of world EDR (economic demonstrated resources) for the mineral. Thorite (ThSiO4) is an isostructural related mineral.
Zircon occurs in many different colors, including red, pink, brown, yellow, hazel, black, or colorless. The color of zircons sometimes can be changed by heat treatment. Depending on the amount of heat applied, colorless, blue, and golden-yellow zircons can be made. In geological settings, the development of pink, red, and purple zircon occurs after hundreds of millions of years provided the crystal has sufficient trace elements to produce color centers. Color in this red or pink series is annealed in geological conditions above the temperature about 350 °C.
Uses
  • Zircons are commercially mined for the metal zirconium, and are used for abrasive and insulating purposes.
  • It is the source of zirconium oxide (ZrO2), one of the most refractory materials known.
  • Large specimens are appreciated as gemstones, owing to their high refractive index. (Zircon has a refractive index of approximately 1.95; diamond's is approximately 2.4.)
  • Zircon is one of the key minerals used by geologists for geochronology .
  • Zircon is a part of the ZTR index to classify highly-weathered sediments.
Occurrence
Zircon is a common accessory to trace mineral constituent of most granite and felsic igneous rocks. Due to its hardness, durability and chemical inertness, zircon persists in sedimentary deposits and is a common constituent of most sands. Zircon is rare within mafic rocks and very rare within ultramafic rocks aside from a group of ultrapotassic intrusive rocks such as kimberlites, carbonatites, and lamprophyre, where zircon can occasionally be found as a trace mineral owing to the unusual magma genesis of these rocks.
Zircon forms economic concentrations within heavy mineral sands ore deposits, within certain pegmatites, and within some rare alkaline volcanic rocks, for example the Toongi Trachyte, Dubbo, New South Wales Australia[8] in association with the zirconium-hafnium minerals eudialyte and armstrongite.
Radiometric dating
Zircon has played an important role during the evolution of radiometric dating. Zircons contain trace amounts of uranium and thorium (from 10 ppm up to 1 wt%) and can be dated using several modern analytical techniques. Because zircons can survive geologic processes like erosion, transport, even high-grade metamorphism, they contain a rich and varied record of geological processes. Currently, zircons are typically dated by uranium-lead (U-Pb), fission-track, and U+Th/He techniques.
Zircons from Jack Hills in the Narryer Gneiss Terrane, Yilgarn Craton, Western Australia, have yielded U-Pb ages up to 4.404 billion years,[9] interpreted to be the age of crystallization, making them the oldest minerals so far dated on Earth. In addition, the oxygen isotopic compositions of some of these zircons have been interpreted to indicate that more than 4.4 billion years ago there was already water on the surface of the Earth.[9][10] This interpretation is supported by additional trace element data,[11][12] but is also the subject of debate.[13][14]
Similar minerals
Hafnon (HfSiO4), Xenotime (YPO4), Béhierite, Schiavinatoite ((Ta, Nb)BO4), Thorite, (ThSiO4), and Coffinite (USiO4) all share the same crystal structure (VIIIX IVY O4) as Zircon.
Zirconium ( /zərˈkoʊniəm/ zər-KOH-ni-əm) is a chemical element with the symbol Zr and atomic number 40. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is used as an alloying agent for its strong resistance to corrosion. It is never found as a native metal; it is obtained mainly from the mineral zircon, which can be purified with chlorine. Zirconium was first isolated in an impure form in 1824 by Jöns Jakob Berzelius.
Zirconium has no known biological role. Zirconium forms both inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. There are five naturally occurring isotopes, three of which are stable. Short-term exposure to zirconium powder causes minor irritation, and inhalation of zirconium compounds can cause skin and lung granulomas.

Characteristics

Zirconium is a lustrous, grayish-white, soft, ductile, and malleable metal which is solid at room temperature, though it becomes hard and brittle at lower purities.[4][5] In powder form, zirconium is highly flammable, but the solid form is far less prone to ignition. Zirconium is highly resistant to corrosion by alkalis, acids, salt water, and other agents.[6] However, it will dissolve in hydrochloric and sulfuric acid, especially when fluorine is present.[7] Alloys with zinc become magnetic below 35 K.[6]
Zirconium's melting point is at 1855°C, and its boiling point 4409°C.[6] Zirconium has an electronegativity of 1.33 on the Pauling scale. Of the elements within d-block, zirconium has the fourth lowest electronegativity after yttrium, lutetium, and hafnium.[8]

Applications

Because of zirconium's excellent resistance to corrosion, it is often used as an alloying agent in materials that are exposed to corrosive agents, such as surgical appliances, explosive primers, vacuum tube getters and filaments. Zirconium dioxide (ZrO2) is used in laboratory crucibles, metallurgical furnaces, as a refractory material,[6] and it can be sintered into a ceramic knife. Zircon (ZrSiO4) is cut into gemstones for use in jewelry. Zirconium carbonate (3ZrO2·CO2·H2O) was used in lotions to treat poison ivy, but this was discontinued because it occasionally caused bad skin reactions.[4]
Ninety percent of all zirconium produced is used in nuclear reactors (in the form of zircaloys) because of its low neutron-capture cross-section and resistance to corrosion.[5][6] Zirconium alloys are used in space vehicle parts for their resistance to heat, an important quality given the extreme heat associated with atmospheric reentry.[9] Zirconium is also a component in some abrasives, such as grinding wheels and sandpaper.[10] Zirconium is used in weapons such as the BLU-97/B Combined Effects Bomb for incendiary effect.

Occurrence

Zirconium has a concentration of about 130 mg/kg within the earth's crust and about 0.026 μg/L in sea water,[15] though it is never found in nature as a native metal. The principal commercial source of zirconium is the zirconium silicate mineral, zircon (ZrSiO4),[4] which is found primarily in Australia, Brazil, India, Russia, South Africa, and the United States, as well as in smaller deposits around the world.[5] 80% of zircon mining occurs in Australia and South Africa.[4] Zircon resources exceed 60 million metric tons worldwide[16] and annual worldwide zirconium production is approximately 900,000 metric tons.[15]
Zircon is a by-product of the mining and processing of the titanium minerals ilmenite and rutile, as well as tin mining.[17] From 2003 to 2007, zircon prices have steadily increased from $360 to $840 per metric ton.[16] Zirconium also occurs in more than 140 other recognized mineral species including baddeleyite and kosnarite.[18] This metal is commercially produced mostly by the reduction of the zirconium(IV) chloride with magnesium metal in the Kroll process.[6] Commercial-quality zirconium for most uses still has a content of 1% to 3% hafnium.

PRICE
$1666646.69/KG OR $757566.67/IB

For more information:

mobile: +2348039721941

contact person: emeaba uche

e-mail: emeabau@yahoo.com

website: www.franchiseminerals.com




Comments

Post a Comment

Popular posts from this blog

AGATE[GEM]

Image
Listing description Agate (pronounced /ˈæ ɡə t/ ) is a microcrystalline variety of quartz ( silica ), chiefly chalcedony , characterised by its fineness of grain and brightness of color. Although agates may be found in various kinds of rock, they are classically associated with volcanic rocks but can be common in certain metamorphic rocks . [1] Detailed description Etymology and history The stone was given its name by Theophrastus , a Greek philosopher and naturalist, who discovered the stone along the shore line of the river Achates ( Greek : Ἀχάτης ) sometime between the 4th and 3rd centuries BC. [2] Colorful agates and other chalcedonies were obtained over 3,000 years ago from the Achates River, now called Dirillo , in Sicily . [3] Ancient use Agate is one of the most common materials used in the art of hardstone carving , and has been recovered at a number of ancient sites, indicating its widespread use in the ancient world; for example, archaeological recovery a...
Read more

ALEXANDRITE

Image
The alexandrite variety displays a color change ( alexandrite effect ) dependent upon the nature of ambient lighting. This color shift is independent of any change of hue with viewing direction through the crystal that would arise from pleochroism . Both these different properties are frequently referred to as "color change", however. DETAILED DESCRIPTION The alexandrite variety displays a color change ( alexandrite effect ) dependent upon the nature of ambient lighting. This color shift is independent of any change of hue with viewing direction through the crystal that would arise from pleochroism . Both these different properties are frequently referred to as "color change", however. Alexandrite results from small scale replacement of aluminium by chromium ions in the crystal structure, which causes intense absorption of light over a narrow range of wavelengths in the yellow region of the spectrum. Alexandrite from the Ural Mountains in Russia is gree...
Read more

TOURMALINE(RUBELITA)GEM

Image
Listing description : MINERALOGY:  The  pink tourmaline , also known as rubelita originates primarily in plutonitas acids, specifically  pegmatite , where forms large  crystals . Through the action of gases containing  boron, from the magma of the host rock, tourmaline it can also arise as inclusion neumatolítica  ( generated depth of the crust (Plutonism) by intrusion of magma, which causes alteration in petrographic composition of the invaded rocks ) then the crystals are included heavily on rock, the  pink tourmaline  consists of different mineral elements, but always has the same structure, the metals are always included in tourmalines and are causing varieties this mineral colors,  the pink tourmaline carries traces of manganese  that is what gives her cute pink. Detailed Description: MYTHOLOGY:  It was found in the Minas Gerais (Brazil)  crystal pink tourmaline (rubellite) of 109 cm.  pink tour...
Read more