Araucarioxylon
arizonicum
Division:
Pinophyta (conifers), Class Pinopsida, Order Pinales, Family Araucariaceae
Geological
Time: Late
Triassic, Norian-Carnian Stage
Size: Fossil
is 65 mm long by 55 mm wide by up to 23 mm thick; weight 134 grams.
Fossil Site:
Winslow, Arizona
Code: PW28
Price: Sold
Description:
This specimen of highly-colored petrified wood from the Chinle Formation
(Norian-Carnian Stage, ~225 million year old) deposits of Winslow,
Arizona comes with a story. Almost 15 years ago, I came across a few
examples of this rare material at a rock shop in southern Utah. I
purchased a sample, and thought little of it. After my return home,
I decided to try to obtain some larger specimens. I had been unsuccessful
until a few years ago. The rich green color is the result of ~2% Chromium
content. While the many types of petrified wood come in a panoply
of colors, only a very few types are green; the only other known to
me is found in Africa. This material comes from a small deposit near
Winslow, and is not known from any other location. Araucarioxylon
arizonicum is the state fossil of Arizona, and is the taxon comprising
some 90% of all specimens found in the Petrified Forest National Monument.
It was a coniferous tree standing some 150-200 feet tall, and some
6-8 feet in diameter. Its closest relatives today are the Monkey Puzzle
Tree of South America and the Norfolk Island Pine. All my initial
specimens are now gone; I was able to acquire a few more this year,
but have been told no more will be available from the field, as it
appears to be played out. This one is al;arger than average specimen;
with increasing size the price can riase dramatically. This one is
(larger) than average specimen; with increasing size the price can
(rise) dramatically. Nevertheless this is stil a most affordable example
given the (scarcity of material). |
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