Who Buys Cubic Zirconia ##HOT##
Whether you are a longtime gemstone lover or looking to buy your first piece of jewelry, you may be weighing up the pros and the cons of cubic zirconia vs diamond. Should you opt for a man made stone or a natural diamond? How do they differ in price and quality?
who buys cubic zirconia
Commonly abbreviated to CZ, cubic zirconia is one of the most popular diamond alternatives (also known as diamond simulants) on the market as it bears a strong resemblance to diamonds. Naturally occurring cubic zirconia is very rare and all cubic zirconia used in jewelry is manmade.
One of the most important factors in the cubic zirconia vs diamonds debate is how much these stones are worth. A quick search online will show you that there is a massive price difference between the two stones.
There are limited places where you can sell a cubic zirconia stone. Your best options are to sell to pawn shops or privately. However, when it comes to diamonds, there are a plethora of buyers. While you are not likely to recoup what you originally paid for the diamonds, you can anticipate receiving about 25% to 50% of its purchase price.
When purchasing a simulation diamond, the quality of cubic zirconia is absolutely critical. Birkat Elyon is renowned as a jeweler for only using the highest grade on the market, Russian Formula. Of the five readily available forms of CZ, Russian Formula is the only type that will catch the light so beautifully; even experienced gemologists have difficulty telling its difference from a real diamond.
Beyond avoiding poor-quality cubic zirconia and mass manufacturing techniques, Birkat Elyon avoids metal plating. Instead, the bands we use in our diverse catalog are available in pure platinum, as well as 100% solid 14K or 18K white or yellow gold. The design options we offer on our site are also selected conscientiously to highlight classic shapes alongside innovative contemporary trends. Keep exploring our site and see for yourself what makes Birkat Elyon the best cubic zirconia (CZ) engagement rings and jewelry you can buy!
Cubic zirconia (abbreviated CZ) is the cubic crystalline form of zirconium dioxide (ZrO2). The synthesized material is hard and usually colorless, but may be made in a variety of different colors. It should not be confused with zircon, which is a zirconium silicate (ZrSiO4). It is sometimes erroneously called cubic zirconium.
Because of its low cost, durability, and close visual likeness to diamond, synthetic cubic zirconia has remained the most gemologically and economically important competitor for diamonds since commercial production began in 1976. Its main competitor as a synthetic gemstone is a more recently cultivated material, synthetic moissanite.
Cubic zirconia is crystallographically isometric, an important attribute of a would-be diamond simulant. During synthesis zirconium oxide naturally forms monoclinic crystals, which are stable form under normal atmospheric conditions. A stabilizer is required for cubic crystals (taking on the fluorite structure) to form, and remain stable at ordinary temperatures; typically this is either yttrium or calcium oxide, the amount of stabilizer used depending on the many recipes of individual manufacturers. Therefore, the physical and optical properties of synthesized CZ vary, all values being ranges.
Under shortwave UV cubic zirconia typically fluoresces a yellow, greenish yellow or "beige". Under longwave UV the effect is greatly diminished, with a whitish glow sometimes being seen. Colored stones may show a strong, complex rare earth absorption spectrum.
The high melting point of zirconia (2750 C or 4976 F) hinders controlled growth of single crystals. However, stabilization of cubic zirconium oxide had been realized early on, with the synthetic product stabilized zirconia introduced in 1929. Although cubic, it was in the form of a polycrystalline ceramic: it was used as a refractory material, highly resistant to chemical and thermal attack (up to 2540 C or 4604 F).[3]
In 1937, German mineralogists M. V. Stackelberg and K. Chudoba discovered naturally occurring cubic zirconia in the form of microscopic grains included in metamict zircon. This was thought to be a byproduct of the metamictization process, but the two scientists did not think the mineral important enough to give it a formal name. The discovery was confirmed through X-ray diffraction, proving the existence of a natural counterpart to the synthetic product.[4][5]
As with the majority of grown diamond substitutes, the idea of producing single-crystal cubic zirconia arose in the minds of scientists seeking a new and versatile material for use in lasers and other optical applications. Its production eventually exceeded that of earlier synthetics, such as synthetic strontium titanate, synthetic rutile, YAG (yttrium aluminium garnet) and GGG (gadolinium gallium garnet).
Some of the earliest research into controlled single-crystal growth of cubic zirconia occurred in 1960s France, much work being done by Y. Roulin and R. Collongues. This technique involved molten zirconia being contained within a thin shell of still-solid zirconia, with crystal growth from the melt. The process was named cold crucible, an allusion to the system of water cooling used. Though promising, these attempts yielded only small crystals.
Later, Soviet scientists under V. V. Osiko in the Laser Equipment Laboratory at the Lebedev Physical Institute in Moscow perfected the technique, which was then named skull crucible (an allusion either to the shape of the water-cooled container or to the form of crystals sometimes grown). They named the jewel Fianit after the institute's name FIAN (Physical Institute of the Academy of Science), but the name was not used outside of the USSR.[citation needed] This was known at the time as the Institute of Physics at the Russian Academy of Science.[6] Their breakthrough was published in 1973, and commercial production began in 1976.[7] In 1977 cubic zirconia began to be mass-produced in the jewelry marketplace by the Ceres Corporation with crystals stabilized with 94% yttria. Other major producers as of 1993 include Taiwan Crystal Company Ltd, Swarovski and ICT inc.[8][5] By 1980 annual global production had reached 60 million carats (12 tonnes) and continued to increase with production reaching around 400 tonnes per year in 1998.[8]
Currently the primary method of cubic zirconia synthesis employed by producers remains to be through the skull-melting method. This method was patented by Josep F. Wenckus and coworkers in 1997. This is largely due to the process allowing for temperatures of over 3000 degrees to be achieved, lack of contact between crucible and material as well as the freedom to choose any gas atmosphere. Primary downsides to this method include the inability to predict the size of the crystals produced and it is impossible to control the crystallization process through temperature changes.[3][9]
Zirconium dioxide thoroughly mixed with a stabilizer (normally 10% yttrium oxide) is fed into a cold crucible. Metallic chips of either zirconium or the stabilizer are introduced into the powder mix in a compact pile manner. The RF generator is switched on and the metallic chips quickly start heating up and readily oxidize into more zirconia. Consequently, the surrounding powder heats up by thermal conduction and begins melting, which in turn becomes electroconductive and thus it begins to heat up via the RF generator as well. This continues until the entire product is molten. Due to the cooling system surrounding the crucible, a thin shell of sintered solid material is formed. This causes the molten zirconia to remain contained within its own powder which prevents it from contamination from the crucible and reduces heat loss. The melt is left at high temperatures for some hours to ensure homogeneity and ensure all impurities have evaporated. Finally, the entire crucible is slowly removed from the RF coils to reduce the heating and let it slowly cool down (from bottom to top). The rate at which the crucible is removed from the RF coils is chosen as a function of the stability of crystallization dictated by the phase transition diagram. This provokes the crystallization process to begin and useful crystals begin to form. Once the crucible has been completely cooled to room temperature, the resulting crystals are multiple elongated-crystalline blocks.[9][10]
When observing the phase diagram the cubic phase will crystallize first as the solution is cooled down no matter the concentration of Y2O3. If the concentration of Y2O3 is not high enough the cubic structure will start to break down into the tetragonal state which will then break down into a monoclinic phase. If the concentration of Y2O3 is between 2.5-5% the resulting product will be PSZ (partially stabilized zirconia) while monophasic cubic crystals will form from around 8-40%. Below 14% at low growth rates tend to be opaque indicating partial phase separation in the solid solution (likely due to diffusion in the crystals remaining in the high temperature region for a longer time). Above this threshold crystals tend to remain clear at reasonable growth rates and maintains good annealing conditions.[9]
Because of cubic zirconia's isomorphic capacity it can be doped with several elements to change the color of the crystal. A list of specific dopants and colors produced by their addition can be seen below.
Due to its optical properties yttrium cubic zirconia (YCZ) has been used for windows, lenses, prisms, filters and laser elements. Particularly in the chemical industry it is used as window material for the monitoring of corrosive liquids due to its chemical stability and mechanical toughness. YCZ has also been used as a substrate for semiconductor and superconductor films in similar industries.[9]
Mechanical properties of partially stabilized zirconia (high hardness and shock resistance, low friction coefficient, high chemical and thermal resistance as well as high wear and tear resistance) allow it to be used as a very particular building material, especially in the bio-engineering industry: It has been used to make reliable super-sharp medical scalpels for doctors that are compatible with bio-tissues and contain an edge much smoother than one made of steel.[9] 041b061a72