Glass is an essential part of our everyday lives, so much so that you probably don’t even realize that it’s there (until it breaks, of course!). But glass is a very interesting material with an even more interesting history. Impress your friends with these little-known facts:

10 Things You Didn’t Know About Glass

  1. Glass is neither a solid or liquid: While there had been a theory that glass is actually a liquid (in which its molecules moved very slowly over time), scientists now consider glass to be what’s called an “amorphous solid”. This is considered to be a state in between a solid and liquid, as glass exhibits traits of both.
  2. Beginning of glass making can be traced back to over 5,500 years ago: The first glass objects (which were beads) are believed to have been produced in Mesopotamia and Egypt. It was considered to be highly luxurious.
  3. Ancient glassware can be extremely valuable: Collectors covet rare pieces of glassware. For example, glassware pieces from renown artist Gabriel Argy-Rousseau are valued up to $30,000!
  4. Not all glass is man-made: There is naturally occurring glass that is created from quickly cooled lava. This volcanic glass is referred to as “obsidian”. It is usually dark in appearance and is quite hard and brittle. This allows obsidian to be used in the creation of extremely sharp knives.
  5. The largest stained hand-made glass window is in Covington, Kentucky: It is located within the Cathedral Basilica of the Assumption (image below), in which its construction dates back to 1895. It spans 194 feet by 144 feet and reaches a height of 81 feet.
  6. Recycling of glass is productive for the economy: Recycling of glass creates jobs. For every 1,000 tons of glass recycled, it creates approximately eight new opportunities.
  7. Recycling of glass helps the environment immensely: One ton of recycled glass saves the equivalent to 10 gallons of oil. In terms of recycling just one glass bottle, the energy saved could power a computer for 30 minutes.
  8. Brown glass has a particular usefulness: This particular tint of glass repels UV light, which comes in handy when it comes to beverage and food containers. This keeps its contents from spoiling due to UV light exposure.
  9. Glass colors are determined by additives: During the glass manufacturing process, the color of the glass can be manipulated by adding various substances and compounds. For example, adding copper oxide makes green and adding cobalt makes blue.
  10. Glass window technology has come a long way: During the Dark Ages (6th to 10th century CE), glass windows in homes were unglazed. This means people had only use wooden shutters to keep out the cold. These windows were also purposely kept small in order to minimize the drafts.