Friday, September 16, 2016

CUBIC ZIRCONIA KNIVES

WEDDING RING OR WEDDING KNIFE

Diamond, is  the best-known and the most sought-after gemstone globally. As such, Diamonds are ever increasing in value and rightfully so because there is nothing in the world that can rival them since they are absolutely unique in all of their characteristics. Their continual hike in price is making it somewhat difficult for those on a budget who wish to invest in Diamonds to even enter the Diamond market. Since this bar for entry into the "Diamond Playing Field" is progressively rising, many a young man who intended to buy his fiancé a genuine rock, is settling for an engagement/wedding ring populated by some Cubic Zirconia (CZ) crystal or the other. 

Be that as it may, this is not because they can't afford a genuine Diamond but rather, with the recent advances in the manufacture of faux Diamonds, a large amounts of Cubic Zirconia set rings that mimic real Diamonds are in their faces wherever they go. You can find Cubic Zirconia jewelry in virtually every Jewelry store, on display at every pawn broker and listed on every jewelry auction. 

They are also extremely pervasive in online catalogues and private sales and even on general online auctions like e-bay, bidz, bidorbuy and propertyroom, etc. The general idea of the CZ pundits, is to flood the market with this low cost or rather a "No Cost" excuse for a Diamond which shouldn't even be associated with the name Diamond. In a nutshell, simulated diamond is actually a misnomer. Man-made diamond is another misnomer and so is faux diamond and lab created Diamond. Some lab Diamonds may be chemically identical to natural Diamonds but are still not real or genuine Diamonds, ask any gemologist.
18ct gold half carat diamond three stone ring worth $2000 US.

Jewelry auctions displaying engagement/wedding  rings made of copper/brass that is 14kt white gold plated, with 1 - 2 ct Cubic Zirconia crystal starts with bids from as little as R1.00 are inundating the internet. This doesn't mean  you won't be outbid for it by some other amor who actually attaches some suedo value to these "stone" and its EP (electroplated) piece of copper. 

Yet, I've seen auctions where 925 silver rings with 1 ct Cubic Zirconia crystals go for R1.00 at the fall of the hammer. However, many young men tend to think because Cubic Zirconias are pervasive and not too expensive (typically 1/10th - 1/5th of Diamond prices) it is OK to buy them. In my opinion they are not OK to buy because they have no real value.

The preposed one tenth to one-fifth of the value of a Diamond of equal size is a fallacy. In reality it's an out-right lie that faux jewelry merchants, scientist  and "femologists"  are trying to sell you. Marketed as an affordable synthetic stone as brilliant as a Diamond,  cut in the same shapes as designs as a Diamond to replicate a Diamond almost exactly ("almost diamond" but not)

To the naked eye, a Diamond and a Cubic Zirconia can look identical. After all, that’s the whole idea, but while a Diamond is said to be a girl’s best friend, that will  never, ever, ever, ever be said about a Cubic Zirconia. The bottom line is, you get what you pay for. So ladies, do yourself a favour and get a diamond education at "What every women should know about Diamonds".

Silver 925 ring with 1.5 carat Cubic Zirconia available on auction from ZAR 1.00
Let me put this into perspective. Diamonds are the hardest naturally-occurring surface  material known to man, thus  much harder than every type of rock, even harder than steel. This implies that a Diamond regardless of how old it is, even the oldest of heirlooms would most likely be in prestine condition, unscratched and looking like it was cut yesterday. Nothing is able to scratch the Diamond except another Diamond. 

This makes it an everlasting jewelry item suitable to be handed down from generation to generation, with the full knowledge that its value will keep-on increasing. Diamond hardness is measured on the Mohr scale which is a qualitative scale that characterizes the scratch resistance of various minerals by the ability of a harder material to scratch a softer material.

For example, Obsidian is volcanic glass and has a hardness of 5.5 on the Mohs hardness scale.  The blade of the average kitchen knife blade is also 5.5 on the Mohs hardness scale. A hardened steel file that can sharpen a knife blade is around 7 on the Mohs hardness scale. Cubic zirconia  has  a hardness  of 8.5 on the Mohs hardness scale thus several times harder than both steel and hardened steel. 

Corundum on the other hand has a hardness of 9 on the Mohs hardness scale and is even harder than Cubic Zirconia. Sapphire and ruby are two varieties of corundum both twice as hard as topaz and has nothing to do with Pokémon Omega Ruby Versus Pokémon Alpha Sapphire Moissanite measures 9.5  on the Mohs hardness scale and Diamond has a hardness of 10 on the Mohs hardness scale, and is four times as hard as Corundum. 

Having said all that, it is more than obvious that a natural sapphire engagement ring or a natural ruby engagement ring is a far, far better purchase in both hardness and value than synthetical manufactured Cubic Zirconia. Cubic zirconia crystals are formed by melting powdered zirconium and zirconium dioxide (ZrO2) together and heating them up to a temperature of 4,982ºF. The produced crystals, so called "gemstones" are then cut to shape to  resemble Diamonds in its various shapes and passed off as almost Diamonds / artificial diamonds. 

However, Cubic Zirconia is 1.7 times denser than a diamond and about 50 percent heavier than natural diamond. So in reality there is no such thing as "almost diamond" and neither is there a thing as "making diamonds" and neither, is there a thing like "artificial diamonds". Diamonds are natural and anything unnatural that resembles Diamonds are not diamonds but are fakes. 

Cubic Zirconia crystals are fake, even though they do not look fake or glassy, they do resemble diamonds yet doesn't even qualify to be called gemstones. Jewelry quality Cubic Zirconia crystals are way overrated and are much more akin to rhinestones (rock crystals originally gathered from the river Rhine) and the modern day varieties of  "rhinestone" manufactured from lead glass, aka crystal glass.


Cubic Zirconia worth a fraction of the diamond weight it represents.
Again in my opinion, Cubic Zirconia doesn't have the necessary hardness to withstand years of wear and tear that Diamond heirlooms should and can withstand. It should rather be put to other uses like making dental crowns, dental implants, bridges  and dentures because Zirconia as a ceramic biomaterial is more suited to making teeth and ball heads for prosthetic implants.  Zirconia ceramics have several advantages over regular ceramic materials, due to their very interesting mechanical properties. 

During the 60's extensive research on the use of Zirconia ceramics as biomaterials started. Since, low-quality zirconia were used as an abrasive in huge quantities  and  refractory Zirconia ceramics were used to manufacture parts operating in aggressive environments, like valves and port liners for internal combustion engines and thermal shock resistant refractory valve parts in foundries. By the turn of the century industrial quality Zirconia blades were used to cut Kevlar, magnetic tapes, cigarette filters because of their ability to withstand wear. 

But today’s main applications of zirconia ceramics is in total hip arthroplasty (THA) ball heads because of its biocompatibility and microstructural characteristics. Cubic Zirconia is relatively hard, though nowhere near diamond but harder than most other materials hence it can scratch glass. 

Different size hip joint  ball  socket (cup and socket)  manufactured from Zirconia ceramics


Prosthetic hip implant with Zirconia bearing coupled to the pelvis
and the ball is attached to a Titanium pin embedded in the femur.
But the newest and latest use for Cubic Zirconia -Zirconium dioxide and Zirconium powder- is to make knives. So in order to perpetuate the "bling industry's facade" that Cubic Zirconia has gem quality value, these knives are not called Cubic Zirconia knives but rather Ceramic Knives.

By dry-pressing Zirconia powder in the shape of a knife and firing it through solid-state sintering, the resultant blade edge is then sharpened by grinding it with a Diamond-dust-coated grinding wheel, producing a knife of 8.8 hardness on the Mohr scale that is harder than any steel knife with a sharp edge that can only be destroyed by cutting material harder than itself. Ceramic knives are substantially lighter than steel knives, and do not conduct electricity at room temperature,  will not corrode because they are non metallic thus also non-magnetic. So, say goodbye to you  magnetic knife holder.  

Cubic Zirconia knives are also strong acid and caustic resistance, highly resistant to bacteria  and have the ability to retain a cutting edge longer than any metal knives. As such,  ceramic knives are better suited for slicing boneless meat, vegetables, fruit and bread. However, since ceramics are brittle, blades may break if dropped on a hard surface and therefore unsuitable for chopping through bones, or frozen foods. In fact, you can have infomercial-like fun slicing and dicing all kinds of food  because they will slice  through foodstuff like a hot knife through butter.  
Cubic Zirconia knives and peeler
Unlike a traditional steel knife blade that can be honed  in  order to keep the  sharp edge, a ceramic knife will stay sharp and retain its cutting edge for  up to 10x longer.  Although a ceramic knife does not need sharpening in the same way as steel, its blade edge will eventually degrade or chip and lose its sharp cutting edge, especially if not protected and stored carefully after use. That means  slicing metal cans are completely out of the question. Today more and more Chef's knives are made of Cubic Zirconia like the black ceramic and  the Kyocera Z206 Advanced Ceramic knifewhich tend to fetch a higher price than the regular kitchen knife.

A Cubic Zirconia knife with an average weigh of 100 grams can be bought for as little as $5.00 whereas a Cubic Zirconia  crystal weighing as little as 1ct is expected to sell for $100.00. Really now! Besides it probably takes longer to press a knife and sharpen it than it takes to polish a tiny CZ crystal. So where does the supposed value of Cubic Zirconia "gemstones" really come from? It's obviously thumb-sucked to con the gullible. The old adage "A fool and is money is soon parted" has never be truer when it comes to Cubic Zirconia jewelry.

Anyway, can you even image the sharpness and longevity of a knife edge if made from genuine Diamond let alone its cost? If this was even possible, what would they actually price the simulated diamond knife at?

1 comment:

  1. Great details about cubic-zirconia-knives.
    thanks for sharing this really the contant is amazing
    informative,interesting , motivative also which was i am looking for . please keep updating step by step .
    zircon vs cubic zirconia

    ReplyDelete