Mount St. Helens Volcanic Ash

The ash in this capsule was violently ejected from Mount St. Helens during the most disastrous volcanic activity in US history.

On the morning of May 18 1980, after weeks of small tremors, a magnitude 5.1 earthquake shook the state of Washington. The quake caused the largest landslide ever recorded according to the USGS, and simultaneously, a lateral explosion from the side of the mountain.

The explosion was rated a 5 on the Volcanic Explosivity Index making it one of the largest eruptions in the 20th century. The sound of the eruption was heard up to 700 miles away.

Some areas were covered in debris, avalanches, and mudflows, and forests were scorched and scoured with hot gases. The ash reached 12 miles high and ash-fall was reported up to 1,500 miles away. 

The ash of every volcanic eruption is unique based on the chemistry, crystal content, temperature and dissolved gases of the erupting magma. Highly explosive eruptions, such as this one, produce brighter ash due to the higher silica content. 

Listing is for one sample of volcanic ash, including acrylic display case.

Diameter = 40.6mm or 1.6”