The Formation of
Thundereggs (Lithophysae)
By Robert Paul
Colburn
Book’s Key Features
·
Complete model of thunderegg formation
based on cristobalite crystallization.
·
The formation of thundereggs related to
obsidian and perlite occurrences, especially lava domes.
·
An extensive photo collection of geodes,
thundereggs, and their inclusions.
·
An extensive list of thunderegg sites in
the west.
·
A detailed discussion of the formation
of thundereggs from flow-banded rhyolitic lava.
·
An extensive review of obsidian flow
formation with a new model presented.
·
A detailed account of how biconoid
thunderegg cores relate to thunderegg genesis.
·
Unusual agate structures such as
flow-stretched and tube lithophysae are documented.
·
A complete Lexicon of geode and
thunderegg structural terms is included.
·
Substantial advice and diagrams are
provided how to properly cut thundereggs.
“I
owe you so much - discussions about thundereggs, thunderegg images…”
Dr.
Peter Woerner, author “Geodes and Thundereggs in Rhyolite”
“You are the Thunderegg Guru!”
“I continue to be amazed at your ability to
synthesize scientific data.”
Doug Moore
“Your insights
on agates…exceed mine. So I just mean to
say thank you.”
John Marshall,
author “The ‘Other’ Lake Superior Agates”
“I have been a
big fan of yours for many, many years.”
Brad Cross,
co-author “Geodes: Nature’s Treasures” with June Zeitner
“Perhaps you now
have my new publications, which would be impossible without your help. Thank you so much!” Peter Wagenblast
"I'm always glad to publicize your work
and to speak well of it."
John Stockwell