Page 38 - visitorGuide

As you make a right down the first floor hallway, you’ll notice something on the ground
foreign to your usual office building. This dinosaur bone has had a few different homes
since its excavation, with its final display location still to be decided.

■ Cast of Dinosaur Footprint
This cast was made in a latex mold taken from the only known fossilized track
of Tyrannosaurus rex. The hallux, or fourth digit on the hind food, is charac-
teristic of T. Rex. The track’s northeastern New Mexico location showed that
T. Rex ranged about 250 miles farther south than previously known.The rocks
that surround the track indicate that T. Rex roamed across a broad river flood-
plain in sub-tropical wetlands dominated by palm trees and ferns, in what is
now the northern part of the state.
Located and donated by Charles Pillmore.

To the left of the dinosaur footprint cast is a case that contains several specimens.
From the top, left-hand corner:

■ Zebra Rock
Zebra rock is named for the distinctive “zebra stripes” that run across it.
It has been found only in the extreme northeast of Western Australia. This
area is now covered by the waters of the Ord River Reservoir, but a few ad-
ditional localities were recorded after 1945. Various explanations for these
distinctive stripes have been proposed, including leaching of iron from the
lighter bands, periodic deposition of iron-rich layers, gravitational separation
in ripple marks, and precipitation of iron oxide.
Collected and donated by Curt Teichert, University of Kansas, Lawrence.

■ Cinnabar
Cinnabar is a low-temperature mineral found near recent volcanic activity,
around hot springs, or in veins or rocks mineralized by hydrothermal solu-
tions. Red, earthy cinnabar like this specimen is found near Terlingua, Texas,
along faults and fractured folds in deformed Cretaceous limestones. Clay lay-
ers above the limestones helped seal in the mineral-bearing solutions that
deposited the ores.
Gift from William J. LeVeque, Claremont, California.

■ Pyrite Cubes
Pyrite is often known as “fool’s gold” because its shiny metallic crystals can
be mistaken for real gold. However, pyrite is often found in close association
with gold and other metals and may be mined for the gold or copper associ-
ated with it. Unlike gold, which is soft, malleable, and golden yellow, pyrite
is hard, brittle, and brassy yellow. It is sometimes tarnished with a brown or
iridescent film of iron oxide.

■ Chalcopyrite and Galena on Dolomite
This specimen is characterized by brassy metallic chalcopyrite crystals and
dark gray metallic galena crystals scattered across a base of pink dolomite
crystals. Chalcopyrite, which often has a tarnish of deep blue, purple, and
black, appears in masses more frequently than in distinct crystals. It is an
important copper ore named from the Greek chalkos (“copper”) and pyrites
(“fiery”).

Galena, which often appears as cubic crystals, is an important ore of
zinc. Zinc has been mined commercially in Missouri, where this specimen
was collected. This state is part of a large tri-state mining district stretching

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