What is glass made of?

The main materials for most consumer glass, which is a type of glass called soda-lime glass, are:
silica or silicon dioxide (commonly known as “sand,” yes, that same sand you find on a beach), sodium carbonate (or soda ash, which is both naturally-occurring and synthetically produced), and lime (calcium carbonate, which is found naturally as limestone, marble, or chalk).

Because of the challenges involved with pure silica glass-making, there are a few other elements that are commonly mixed into the silica blend to make it melt more quickly and easier to mold. These elements include:

Sodium (Na) as sodium oxide (Na2O)
Calcium (Ca) as calcium oxide (CaO)
Lead (Pb) as lead oxide (PbO)
Potassium (K) as potassium oxide (K2O)

Additionally, there are elements that can be added to make the glass different colors. These include:

Iron (Fe) to color red
Copper (Cu) to color light blue
Manganese (Mn) to color purple
Cobalt (Cu) to color dark blue
Gold (Au) to color deep red

Another common and more durable form of glass is borosilicate glass.

In this type of glass the silica is slightly increased (70–80%), the soda ash is decreased and in part replaced with boric oxide (7–13%), which has the effect of increasing its durability and thermal shock resistance. Thus it it less prone to breakage with fast extreme temperature changes.

Many of the glass products we carry are made of borosilicate glass, such as our airtight glass containers.

Tempered glass

Tempered glass is about four times stronger than “ordinary,” or annealed, glass.
And unlike annealed glass, which can shatter into jagged shards when broken, tempered glass fractures into small, relatively harmless pieces.

As a result, tempered glass is used in those environments where human safety is an issue. Applications include side and rear windows in vehicles, entrance doors, shower and tub enclosures, racquetball courts, patio furniture, microwave ovens and skylights.