reply to post by frugal
The wiki article on the Baigong pipes references them, but here are abstracts about them:
aapgbull.geoscienceworld.org...
and:
jsedres.sepmonline.org...
Navajo Sandstone and Utah respectively, also found in Louisiana:
jsedres.sepmonline.org...
Really sort of complex, but basically explaining they are geological formations.
In the Louisiana case, fossilized remains of tree roots.
The Navajo Sandstone formation also features similar artifacts to the Klerpdorf spheres, again, fully natural formations as well.
edit on
20-11-2010 by RuneSpider because: (no reason given)