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About Sea Glass

The History of Sea Glass
IMG_rare sea glass

We know that there is naturally made glass such as obsidian or volcanic glass which is molten rock that has quickly cooled, becoming rock in a glassy state, but historians say it is difficult to ascertain exactly when glass was first manmade, the general consensus being that it first appeared around 4000 years ago in Mesopotamia

Over the centuries glass has changed in colour and property, In 1200 BC the Egyptians developed a technique of pressing it into moulds, in the 1st century it was the Syrians who were responsible for glass blowing techniques, which made glass more affordable and it was the Romans who started to incorporate it into everyday use.

I haven’t had the pleasure of finding any pieces from these ages that I know of, but I have found pieces from the 1700/1800s which is commonly known in the sea glass world as ‘Pirate Glass”.  This glass is thick and initially looks black. It is therefore tricky to find amongst the pebbles, but when held up to the light is dark olive in colour. Black glass is hand blown and dates back as far as the 1700s. It was commonly used for beer and liquor bottles until about 1870.

There are other colours such as amber and purple that are also referred to as black glass and date from the 1800s. I do have amber and when I find these old pieces, it gives me a huge sense of how far we have come in glass making.

Safety glass is another common find, at least on the beaches I explore and I have about three large jars full, which I am not sure what to do with yet.  It has been around since the early 20th century and was used where glass would cause a hazard if broken.  Commonly found in cars, doors and cookware. 

It’s development was purely by accident in 1903 when a French scientist dropped a glass flask of cellulose nitrate and saw that liquid helped the glass  keep its original form. 
In the early 1900s, German scientist Rufolf Sieden developed tempered glass. 


It’s probably a great time to mention that in the 1900s grey glass was very common.  It is one of my favourite colours to find.  At that time, glass makers were trying to develop a clear glass, but certain types of sand had impurities which they found difficult to remove and gave it a grey colour.  For sea glass hunters like myself, it’s an absolute joy to find these pieces as its colour brings more joy than the clear glass they were trying to master.

Since the 1920s, glass techniques have been refined and moulded.  All over the world there are amazing examples of artistic expression in the form of sculptures, stained glass window jewellery, storage containers and tableware. 

Amongst the sea glass hunters we use what was once discarded and make it beautiful again and essentially recycle it to give it a new purpose.

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