A Mountain of Glass

Not far from where we live is a little known geologic formation called Little Glass Mountain. This mountain is accessible by traveling about 20 miles of California back roads, some gravel, through the Modoc and Klamath National Forests. Little Glass Mountain is not really that little. Just over a thousand years ago lava oozed from the Medicine Lake Volcano forming this mountain almost 8,000 feet tall. As lava moved slowly down slope, it built up a spectacular high flow front of broken obsidian and pumice. Glass flows are an uncommon and intriguing phenomena. As pictures commonly cannot show we stood in amazement looking at more obsidian than we had ever seen in our lifetime, in fact more than we ever thought existed on the planet. This place must be a geologists dream come true.

The one mile trail head begins at the edge of a Forest Road
The flow is thick, nearly 100 feet high.

The summit of Little Glass Mountain in the background. 



The black glass is obsidian and the grey rock is pumice. We stayed on the trail for safety, since the glass is as sharp as razors.



Red hues are the result of weathering or oxidation during eruption.



A large chip out of an even larger obsidian boulder

Virginia had a hard time not over collecting rocks.
Her nickname was Lucy (The Long Trailer).

Obsidian mounds piled up as if by African termites.

We ended our tour with a late lunch at Medicine Lake
inside the caldera of the same name.