What's The Difference Between Glass And Diamond and Crystal?

I've been wondering in a shop just looking at the jewels they have and something caught my attention, it's the models that's made out of diamonds/crystals/glasses. So then I've been wondering how can I tell if it's a diamond, crystal or glass?


I need to have the details what a diamond, crystal and glass looks like or what kind of difference they have!|||It's all about bonding!





First, let's start with defining what is and isn't a crystal. A crystal is any solid with a regular and repeated "crystal structure". This means that all the atoms in the material are lined up in a regular and repeated way. Basically a crystal is formed by a unit structure called a "cell" and this cell is repeated over and over. Glass is not a crystal as its atomic structure is disordered (but more on that later).





Crystals are differentiated in two ways: composition and bonding. Graphite and diamond are both the same composition and they are both crystals but because the bonding is different one is used as the "lead" in pencils while the other is very hard (and shinny so it's good for rings). The bonding in diamond is called sp3 hybridization of carbon. This is a fancy way of describing the state of covalent bonding of carbon. I won't go into great detail but suffice it to say, because of the stregth and directionality of that bonding, diamond is EXTREMELY hard. Graphite is hexagonally close packed configured carbon, which means its bonded in hexagon sheets with weak bonds connecting the stacked hexagons. These weak bonds between layers allows for it to shear (slide) off easily making it ideal as a writing utensil.





Many different types of crystals exists but I'm guessing you meant 'what is the material commonly called "crystal"?' when you asked this question.





This leads us to glass...





I said before that glass is non-crystalline and that's true, but what you know of as "crystal" (like stemware and expensive knick-knacks) is actually glass, making it one of the most incorrectly named objects of all time!





Glass can be many compositions but it generally starts as sand (SiO2) Soda-ash (Na2O) and Lime (CaO), which is why most commercial glass is called soda-lime-silicates. These compounds are mixed and heated to melting. The trick to making a glass is cooling this melt before the atoms can line up in a crystalline manner. We would say the thermodynamics of cooling must overtake the kenetics of crystallization. Thus, after cooling you have a material with a non-crystalline atomic structure. Basically, it's as if you froze the disordered liquid structure on place.





As I said, the term "crystal" referes to material that is actually a glass but it has as much as 25% Lead added to increase the refractive index, which makes more light reflect off the glass surface. This makes the glass more shinny, which I guess is appealing to people, though I wonder if it would be as appealing if people knew how much lead was in the glass!





As for telling the difference between them, you could do several things, though unfortunately they tend to be somewhat destructive. Hardness testing measures the strength of the surface bonding, which is different between most materials. Testing the heat capacity difference at phase transitions in a Differential Scanning Calorimeter would also tell the difference. But the best way is to have a trained eye examine the material under a microscope. You will be able to see crystallographic growth directions under a microscope which can tell you about the crystal, and if there aren't any... it's a glass.





So as you can se the field of materials science is vast but what differentiates materials usually comes down to the way a material is bonded.|||Checking the chemical composition is a good ised.


Diamonds are pure carbon. Artificial ones now have colors. They are made under very high temperature and pressure.


Glass is silicon dioxide, SiO2, with additions for color. Glass can be melted and shaped.


Crystals can be any mineral. They come in many colors.


Many chemical compounds make crystals. Many minerals can be identified by their shape crystal.





NaCl, sodium chloride is a cubic crystal but is not used in jewelry as it woud dissolve when it got wet.





Check Google jewelry/crystal, there are hundreds of types.|||Go look for the chemical compositions and the refrective index of those 3 .





But I would say that diamond can scratch anything (it's the hardest after all!), crystal can scratch glass and glass well.... it'll cut your hand =.=|||basically the hardness index of the three materials.|||Glass can have many compositions. A common practice used to be to just make it out of melted sand, which is SiO2 (quartz). Today, though there are many more additives to the silica to make it stronger and shatter resistant.





Diamonds are a form of carbon. They form under high heat and pressure deep in the crust. It is the hardest natural substance.





When you say crystal, I assume you mean something like Swarvoski crystal. This is know as lead crystal and lead oxide has been added to regular glass to give it a higher index of refraction so it will "sparkle" more when faceted.|||1.crystal is salt =NaCl,and similar molecular structure shape.


2.Glass is made off silicon sodaJena Cam谋.


3.Diamond is cubic carbon crystalization and hardest object as know.