Glass is a non-crystalline, amorphous solid that is often transparent and has widespread practical, technological, and decorative uses. Glasses are made from silicates, but they may also contain other oxides and even metal oxides. The word “glass” comes from the Old English glæs which refers to the material we now call glass.
The first glasses were made more than 5,000 years ago in Mesopotamia and Egypt. In fact, some of the earliest known glass objects date back to around 3100 BCE! Early glasses were used for beads, ornaments, and small vessels. It wasn’t until around 200 BCE that glass blowing was developed, which allowed for the production of larger objects such as windows and bottles.
Since then, glasses have been an important part of human civilization. They’ve been used for everything from tools to art to adornments. Today, modern glasses are made from a variety of materials including sand (silica), soda ash (sodium carbonate), limestone (calcium carbonate), dolomite (calcium magnesium carbonate), potash (potassium oxide), borax (sodium borate), aluminum oxide, lead oxide…and even gold!
There are two main types of glass: float glass and sheet glass. Float glass is manufactured by floating molten glass on top of a pool of molten tin. This method gives the sheet a very flat surface on both sides making it ideal for use in windows etcetera. Sheet glass is produced by rolling molten glass out into large sheets which are then cut down to size according to customer specifications; this type of glass is usually thicker than float glass since it doesn’t go through the same “floating” process during manufacturing
One common myth about glasses is that if you drop a penny in front of a window pane and it falls straight down rather than sideways then your window is made from real leaded crystal – this simply isn’t true! All modern commercial windows are made from either soda lime silicate or tempered safety glazing materials like annealedfloat or heat strengthenedfloat; neither contains any lead at all so there’s no way to tell just by looking at them
Despite their long history and ubiquitous presence in our lives today, we still don’t know everything there is to know about these enigmatic substances we call ‘glass’. Researchers continue to explore new ways to utilize existing technology while also developing brand new applications for this fascinating material