Glass vs Crystal: differences, uses and secrets

Within glassworks, two materials often emerge with particular prominence: the glass and crystal. At first glance, to the uninitiated in the field, they may appear very similar, but in reality they conceal a number of significant differences that define their quality, use, and value.

Beyond natural transparency, discovering glass

Glass is by far one of the most widespread and most present materials in our daily lives: windows, doors, furniture elements, but also mirrors, utensils and containers... in the world around us, glass is chosen for multiple applications. The trend to reduce waste and environmental impact will lead to an increasing use of this material, thanks to its inherent peculiarity That it can be re-melted and reused endlessly.

The creation of glass is achieved by melting a mixture of silicates at high temperatures, then subsequently allowed to cool; within this mixture are quartz and other chemicals such as silicon oxide, boric anhydride and phosphoric anhydride known precisely as “vitrifying substances”. This processing results in a homogeneous material with a random, noncrystalline molecular structure that, when cooled, becomes rigid without crystallizing.

Glass, if not properly treated, is very fragile in nature and tends to break easily into several sharp fragments. For this reason, especially in residential settings or furniture, it is preferred to the tempered glass defined as such precisely because it undergoes a “Tempering” process that makes it stronger and more elastic and which, if broken, produces fragments with blunt corners.

Beyond elegant brilliance, discovering crystal

Referred to as a “crystal” because of its lattice structure of regularly arranged atoms and molecules, this material has A significantly higher refractive index than glass which makes it extremely brilliant. To achieve this particular “crystal lattice,” the calcium components found in ordinary glass are substituted for lead oxide and then the normal process of melting and subsequent cooling is followed.

Thus starting from a chemical composition very similar to that of glass, crystal differs in certain characteristics of luster, transparency, elasticity and sonority which are conferred by the presence of lead oxide. In fact, lead is the main element that makes crystal shinier because it has greater refraction and, when touched, is more sonorous than glass. To be crystal, the material must contain at least 24% lead: this important percentage allows it to take on extremely high strength, which is why crystal objects may be thinner than glass objects-but they are also more delicate.

Brilliance, sonority, cut, and preciousness are thus the main defining characteristics of crystal: its greater density and purity make it brighter than glass, the presence of lead causes crystal to produce a crisp, prolonged sound when touched, and it is easier to cut precisely to create complex decorative patterns. Last but not least, thanks to these characteristics of it. crystal has become an emblem of luxury: its value-both perceived and economic-is significantly higher than glass.

In addition to this “proof,” in order to distinguish simple glass from the more elegant crystal, it is possible to check whether the object has the appropriate label: all European countries have adopted an EEC regulation (69/493) which has grouped the different types of glass with precise labeling that allows the end customer to distinguish crystal from glass with absolute certainty.

Crystal grinding: how best to perform it

Compared with glass grinding, the crystal grinding must take into consideration a number of factors including:

• Material hardness
  The greater hardness of crystal requires stronger equipment and harder abrasives
• Accuracy
  Imperfections and smudges are more obvious in crystal, so more attention to detail is needed during the manufacturing process
• Type of grinding wheel
  The grinding wheels usually used for crystal are finer and can be made from more valuable abrasive materials
• Use of additives
  In some cases additives may be added to the crystal during the grinding process to improve transparency, brilliance and coloration.

Although they are the same process, in order to achieve optimal crystal grinding, it is essential to understand the inherent differences between the two materials so that the most appropriate tools can be used and a highly satisfactory result of excellent quality can be obtained.

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