Rock star: Obsidian

May 13, 2015

OLYMPUS DIGITAL CAMERA

Did you know that most of the obsidian you see for sale is actually fake?  That’s the reason it has taken us so long to find some that we are willing to have in the shop.

Some of the newest rock money can buy, this obsidian is only 129 years old from the Mt Tarawera volcanic eruption in June 1886 in the Bay of Plenty Region, New Zealand.  Formed at the margins of rhyolitic flows it also contains pumice and perlite inclusions formed by contact with groundwater.

In the classroom, explore differences in structure compared to other rocks from felsic lava such as pumice.

Colour: black to black/green

Fracture: conchoidal

Mohs hardness :5-6

This obsidian has been collected for us by a geologist in New Zealand, so we will guarantee that it is the real deal and absolutely not fake so it has the Angus Seal of Approval