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Photo Gallery - Mineral of the Month

 

MINERAL OF THE MONTH

July 2009 - Obsidian Needles

Obsidian Needles

Obsidian is a dark volcanic glass. It is rich in silica and breaks with a very sharp conchoidal fracture. It is formed by the very rapid cooling of viscous acid lava.

Although black is the most common color, it is also found in a variety of other colors from mahogany to red, green, pink, blue, silver, and rainbow. Obsidian Needles are a naturally occurring fracture. This one was dug out of the mountains near Davis Creek, California. Over thousands of years the razor sharp edges of the original fractured pieces have been smoothed by the minerals in seepage from rain and snow melt. Native Americans used these “needles” for leather work tools, hunting weapons, ornamental designs, and cutting utensils.

Obsidian is considered to be one of the main protection stones by many of the Native American tribes.


Mineral of the Month Archives

May 2007 Rainbow Fluorite

June 2007 Lake Superior Michipicoten Agate

July 2007 Labadorite

August 2007 Rain Flower Agate

Fall 2007 Malachite

December 2007 Nepheline Syenite

January 2008 Native Copper

February 2008 Amazonite

March 2008 Lake Superior Agate

April 2008 Shadow Agate

May 2008 Apohpylite

June 2008 Ocean Jasper

Summer 2008 Marra Mamba Tiger's Eye

September 2008 Mohawkite

October 2008 Mexican opal

November 2008 Prehnite

December 2008 Picture Jasper

January 2009 Sea Shell Jasper

February 2009 Polychrome Jasper

March 2009 Selenite Desert Rose

Spring 2009 Coyamito Agate

July 2009 Obsidian Needles

August 2009 Goethite

September 2009 Banded Iron Formation

Fall 2009 Fairburn Agate

February 2010 Kentucky Agate

March 2010 Fossilized Dinosaur Bone

April/May 2010 Kentucky Agate


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Gitche Gumee Museum.
E21739 Brazel Street
Grand Marais, Michigan 49839

 


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