Difference Between Glass and Crystal

The key difference between glass and crystal is that the glass has an amorphous structure whereas the crystal has a crystalline structure.

Glass and crystals have many important uses due to their special chemical and physical properties. They have very high melting points and unique optical properties. Both are very rigid material and have complex structures.

CONTENTS

1. Overview and Key Difference
2. What is Glass
3. What is Crystal
4. Side by Side Comparison – Glass vs Crystal in Tabular Form
5. Summary

What is Glass?

Glass is a solid inorganic material. This material has a long history, which extends over the period of 3000 BC. There is evidence that at around 2500 BC, the Egyptians used this material. They have used glass to make beads, mirrors, and windows back then, and even now, it’s a material with a large number of applications.

Moreover, glass is a hard material, but fragile, so it breaks into sharp pieces when fallen. Above all, it is primarily made with sand (silica/ SiO2), and bases like sodium carbonate, and calcium carbonate. At high temperatures, these materials melt together and when we cool the mixture, rigid glass forms rapidly. In other words, when we are cooling the mixture, the atoms arrange in a disordered manner to produce glass; thus we name it as an amorphous material.

However, atoms can have a short-range order due to chemical bonding characteristics. Normally, silica melts at about 2000 ^oC, but the addition of sodium carbonate reduces its melting point to 1000 ^oC. Depending on the added chemicals, type of glass varies. Usually, glass is transparent, and it may have colours according to the added material in the synthesizing process. Moreover, it can refract, reflect or transmit light, therefore, used to make lenses and windows. Glass doesn’t conduct electricity, but it can conduct heat. The reactivity of glass with different materials is minimum, thus, making it a good storing and packing material. It also doesn’t leach chemicals. Furthermore, this material can withstand relatively high or low temperatures. With very high heat, we can melt it again, so it is easy to recycle.

What is Crystal?

Crystals are solids, which have ordered structures and symmetry. The atoms, molecules or ions in crystals arranged in a particular manner, thus, have a long-range order. Generally, these materials are naturally occurring on earth as large crystalline rocks, such as quartz, granite. Living organisms also form crystals. For instance, calcite forms as a product of mollusks.

Moreover, the water-based materials such as snow, ice or glaciers are also crystals. We can categorize crystals according to their physical and chemical properties; such as covalent crystals (e.g., diamond), metallic crystals (e.g., pyrite), ionic crystals (e.g., sodium chloride) and molecular crystals (e.g., sugar). Apart from that, these materials can have different shapes and colours; hence, they have an aesthetic value. Also, it is believed to have healing properties; thus, people use them to make jewellery.

What is the Difference Between Glass and Crystal?

Glass is a solid inorganic material that we use in our daily life while crystals are solids that have ordered structures and symmetry. The key difference between glass and crystal is that glass has an amorphous structure whereas crystal has a crystalline structure. Moreover, glass only has a short range order of atoms while crystals have a long-range order. Another important difference between glass and crystal is that glass is a man-made product whereas crystals may occur naturally on earth.

Summary – Glass vs Crystal

Crystal is the ordered structure of glass. In other words, glass has an unordered atomic arrangement. Hence, the key difference between glass and crystal is that glass has an amorphous structure whereas crystal has a crystalline structure.

Reference:

1. “Glass.” Wikipedia, Wikimedia Foundation, 6 Nov. 2018. Available here 
2. “Crystal.” Wikipedia, Wikimedia Foundation, 30 Oct. 2018. Available here 

Image Courtesy:

1.”Cups2″By MarcellusWallace – Own work, (CC BY-SA 3.0) via Commons Wikimedia  
2.”Amethystemadagascar2″By Didier Descouens – Own work, (CC BY 3.0) via Commons Wikimedia