Glass is a material created by man from the combination and fusion of minerals at high temperatures, which results in a transparent, brittle, hard and moldable by-product.
Crystal is any naturally occurring solid formed from chemical processes that create a crystal lattice, which is an ordered, symmetrical structure of atoms and molecules.
The difference between glass and crystal is that glass is created with human intervention, while crystal is a form in which the atoms and molecules of solid bodies are grouped.
Glass Crystal Definition Amorphous and moldable material created from the fusion of compounds at high temperatures. Solid material formed from the crystallization process. Origin Found in nature (cooled volcanic lava). The human being began to create it in the Upper Paleolithic. It is found in nature. Sodic-calcic types. Lead (mistakenly called “crystal”). Borosilicate. Silica. cubic system. Tetragonal system. orthorhombic system. Hexagonal system Trigonal system Monoclinic system Triclinic system. Examples Thermal cookware. Lab’s material. tinted windows. Iron (Fe). Copper (Cu). Manganese (Mn4+O2) How it is recycled Classification. Separation. Crushed and melted.
Glass waste goes in the green container.
If you mean lead glass, commonly called “crystal”, it cannot be recycled.
Lead glass waste goes into the gray bin.
What is glass?
Obsidian, natural glass originated by the cooling of volcanic remains.
Glass is a solid and amorphous material, created from the fusion of compounds such as silicon oxide (SiO2), sodium carbonate (Na2CO3) and calcium carbonate (CaCO3), among others.
In nature, glass can be found:
like obsidiana bright, strong and sharp rock obtained by cooling volcanic lava.
as tacticswhich are glasses from meteorites that impacted on Earth and which, due to their origin, are very rare.
The use of glass in its natural form is not as common and has been reduced to the production of ornamental objects, hence man-made glass is much more popular.
On the other hand, industrial glass is classified into several types, depending on its chemical composition.
Types of glass and their uses
There are 4 types of glass, depending on the components that make it up.
Soda-lime glass
It is made up of calcium, sodium and silica. It is very easy to melt and that is why it is the cheapest type of glass on the market.
For a long time it was recommended to avoid soda-calcium glass for the manufacture of refractory containers for gastronomic use, because it did not tolerate changes in temperature and tended to break. However, this characteristic has been modified with the incorporation of a greater amount of silica, which gives it greater resistance.
An example of soda-lime glass can be found in automobile glass.
lead glass
It is a glass that is manufactured by substituting sodium and calcium for lead. It is very easy to cast and expands, which means that it expands when melted. It also has a refractory quality and absorption of UV rays.
Lead glass is often called lead crystal, or simply crystal. However, this is just a commercial, since glass is not a crystalline structure, therefore, crystal objects do not exist.
In everyday life, lead glass is present in glasses, glasses or tableware.
borosilicate glass
It is composed of silica and boron oxide. It does not melt so easily, it has a great refractory capacity and its expansion capacity is limited, which is why it is used to manufacture laboratory and kitchen materials, since they can withstand high temperatures without expanding and without the risk of breaking due to thermal shock.
An example of application of borosilicate glass are refractory trays and containers.
silica glass
It is the most difficult glass to melt, since very high temperatures (more than 1500 °C) are required, as well as very sophisticated and expensive techniques to transform it into a final product.
Examples of silica glass can be seen in objects that require prolonged exposure to high temperatures, such as oven linings or laboratory tubes.
What is the crystal?
Crystallized water in a snowflake
The crystal is a solid, transparent structure, with an ordered, symmetrical molecular arrangement and regular geometry. It is abundant in nature, and is formed from crystallization, a process in which atoms or molecules form bonds to create an elementary unit called unit cella structure in the shape of a cube or parallelepiped.
In everyday life, the term “crystal” is used to refer to lead glass, used in the manufacture of objects such as glasses and goblets. This denomination is incorrect, since glass is a material with an asymmetric and disordered molecular structure, therefore, it is about two different materials.
Unit cells are classified into several groups based on their characteristics. These groups are known as crystal systems.
crystal systems
According to the length of the sides of the unit cell, the arrangement of their axes and angles, crystals are classified into seven major crystal systems.
1. Cubic system
The unit cell is in the shape of a cube. It is the simplest configuration of the system and one of the most common in nature. Examples of cubic crystal systems are iron (Fe) and copper (Cu).
2. Tetragonal system
The unit cell has the shape of a parallelepiped, which results in a figure with a base of three axes with angles of 90 degrees. An example of a tetragonal crystalline system is manganese oxide (Mn4+O2).
3. Orthorhombic system
The unit cell has the shape of an elongated cube with three right angles and three edges (segments that limit the faces of the cube) with different lengths. Topaz is a mineral that belongs to this crystalline system.
4. Hexagonal system
The unit cell has the base of a hexagon and the symmetry of a prism, with three axes of 120°. An example of a hexagonal system is graphite, one of the forms in which carbon (C) occurs in nature.
5. Rhombohedral system
The unit cell has three right angles and three equal edges. Ruby is an example of a trigonal crystal system.
6. Monoclinic system
The unit cell has two 90° axes and their edges are of different lengths. Mica is a mineral that has this configuration.
7. Triclinic system
The unit cell has three unequal axes, as do their lengths. An example of a triclinic system is albite (NaAlSi3O8), a mineral from the group of silicates.
How is glass and crystal recycled?
Although they are treated as synonyms, glass and crystal are two different elements. Glass is a material resulting from the fusion of various compounds, such as silica, while glass is a molecular structure.
glass recycling
Glass recycling consists of taking advantage of glass waste to turn it into raw material for the production of new products. To do so, you need to follow these steps:
Classification: glass is classified according to its type (if it is soda, lead, borosilicate, etc.)
Separation: once classified, the glass is separated from any other material that has not been previously discarded (small pieces of plastic, metal, etc.)
crushed and melted: clean glass is crushed and melted together with other compounds such as sodium, limestone and silica to obtain the raw material that will be used in the production of new glass products.
The glasses suitable for recycling are those that come from bottles, containers and glasses and are put in the green bins. Laminated, broken glass, light bulbs or lamps cannot be recycled and goes in the gray container.
glass recycling
When you talk about glass recycling, you are really talking about recycling lead glass. In this case, objects made with this material cannot be recycled and they go in the gray container.
Recycling the “crystal” or lead glass in the green containers generates serious damage to the environment. Lead is a compound that is harmful to health, and if it is not properly separated in recycling centers it ends up in smelting furnaces. There it will be mixed with other remains of glass with which bottles or other objects will later be made.