http://www.nmsu.edu/~geology/zuhl/zuhl.html
The Joan and Herbert Zuhl Library at New Mexico State University houses their
30 year collection of petrified wood, fossils, and minerals.
http://www.nps.gov/
General information about all of our national parks. Click on the Petrified
Forest National Park link.
http://www.spirit-stones.com/type_wood.html
Ancient Chinese references to petrified wood, “muhuashi”. Revered
as far back as the Tang and Ming Dynasties, it is considered to be one of
the Chinese Scholars’ Rocks/Spirit Stones.