Page Banner

United States Department of Agriculture

Agricultural Research Service

ARS Photo Library

Download a high-resolution (300dpi) digital image here

Image Number D115-1

These rare-earth oxides are used as tracers to determine which parts of a watershed are eroding. Clockwise from top center: praseodymium, cerium, lanthanum, neodymium, samarium, and gadolinium.

Photo by Peggy Greb.



640 pixels wide: (D115-1.jpg)




Please visit our Image Gallery
Last Modified: 5/23/2006