Gretchen M. Alexander
"Crinoids and Magnetite"

Pictures

Statement

Process

 

Pictures

 

 

(Photos by Patrick Fraser)

Return to Top

Statement

Remnants of life in an ancient sea and an iron rich mountain range ground to tiny particles are found in abundance in the pebbles and sand of a Lake Michigan Beach. These tiny particles provide evidence of the great changes our region has undergone since being covered by a shallow sea in the Ordovician period (490 to 443 million years ago) and the more recent Glaciers that moved across the area four times between
1.5 million and 20,000 years ago.

Crinoids, or Sea Lilies, were an abundant animal life form in the long ago seas. Crinoids looked like plants with a stem of discs held to the sea floor by roots, with the mouth atop the stem surrounded by arms to capture food. Upon dying, the plates and discs fell apart, sinking to the sea floor where some fossilized. Discs of Crinoid stems are still found today washed up along with pebbles on the shore.

The dark streaks appearing in the beach sand on my piece, are composed of very fine black particles of Magnetite, magnetic iron oxide sand, formed by the series of glaciers advancing and retreating across the Canadian Shield Range. The glaciation process broke apart the metamorphic and igneous rocks containing the iron oxide, and distributed the resulting Magnetite particles.

Return to Top

Process
     
     
     

 

Return to Top

 


Contact Webmaster at WomensJourneysinFiber at gmail.com

© All Rights Reserved
All text and images are the copyright of Women's Journeys in Fiber or the individual artists. Reproduction of any kind is prohibited without prior written consent.

Last Updated November 7, 2018