23-year old Sarah Pickin discovered the Neolithic gum during a dig in north-west Finland recently.

Her finding is especially significant as it shows that chewing gum existed even 5,000 years ago.

The lump of birch-bark tar, complete with visible tooth marks, has now been sent for analysis where it is expected to be carbon dated at around 3000BC.

"I had heard of ancient chewing gum being found before on previous European digs so when I found it in the trench, it was the first thing that crossed my mind," the Scotsman quoted Pickin, as saying.

"However, it looks just like a dirty piece of modern chewing gum with no smell or taste and I was also worried it could have been a bit of fossilised poo, so I asked a few of the other students to make sure.

"Thankfully they agreed that it was birch-bark gum and it's now away to be carbon dated and have the teeth marks analysed before it goes on display," she added.

Pickin’s tutor at Derby, Professor Trevor Brown, a heritage and conservation expert, said: "Birch-bark tar contains phenols, which are antiseptic compounds.

"It is generally believed that Neolithic people suffering from gum infections found that chewing this stuff helped to treat the condition.