Obsidian |
Obsidian spear-head |
Other forms of naturally-occurring glass are:
- pumice, a glassy foam produced from lava
- fulgurites, glass tubes formed by lightning striking sand or sandy soil
- tektites, lumps or beads of glass probably formed during meteoric impacts.
Ancient glass on the Bellarine Peninsula?
We have yet to find any mention of naturally-occurring glass on the Bellarine. However, there is a chance that somewhere in Australia there is natural glass formed by an asteroid impact.
Australia has 26 confirmed craters created by asteroids between five thousand and two billion years ago; and it has another 6 unconfirmed craters. (The confirmed
craters are listed in
the Earth Impact Datbase, maintained by the University of New Brunswick’s
Planetary and Space Science Centre.)
Natural glass in the Sahara |
The same scientists believe that 800,000 years ago, another asteroid exploded just above the earth into a series of fireballs that melted the ground into black glass in Thailand, Vietnam, Cambodia and southern China.
Source:
“Tutankhamun’s Fireball”. Horizon series. BBC.
2006.
https://www.youtube.com/watch?v=FO61IKwRpis
https://www.youtube.com/watch?v=FO61IKwRpis
What next for the Bellarine's glass-related history?
Natural glass from the Sahara |
Australia has certainly been hit by asteroids; and it's likely that asteroids were implicated in forming natural glass. However, the scientists investigating the natural glass in Egypt and in S-E Asia note that in neither case is there a crater to serve as evidence of the asteroid's impact. Instead, they believe, the asteroids exploded above ground, leaving no crater, but nonetheless melting the ground under them into glass. So while it's possible that humans in what is now Australia used asteroid-formed glass in the past, proof awaits the first finding of natural glass.
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