Re: Oregon Rock ID help From Cristmas Valley
It looks like ferricrete to me. It is probably geothite/hematite cemented sand/gravel. Sometimes it forms as weathering product from buried sulfide deposits. It can be an indication there is a mineral deposit nearby that has or had weathering sulfides like pyrite in it.
Are there any old mines within the valley or drainage system you live in? Within a mile or two?
From Keith - March 08, 2008 at 19:06:55