
sedimentary
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Hardness: 5-7 (depending on mineral replacement); Color: brownish-tan to black; Luster: dull to vitreous; Structure: retains the bone's original cellular morphology in a rock matrix.
- Hardness
- 5-7 (depending on mineral replacement)
- Color
- brownish-tan to black
- Luster
- dull to vitreous
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-7 (depending on mineral replacement); Color: brownish-tan to black; Luster: dull to vitreous; Structure: retains the bone's original cellular morphology in a rock matrix.
Formation & geological history
Formed via permineralization where minerals (like silica or calcite) precipitate into organic pores. This specimen appears to be from the Late Cretaceous period (approx. 66-68 million years ago).
Uses & applications
Scientific research, museum display, and high-end private collecting.
Geological facts
T. rex had one of the strongest bite forces of any terrestrial animal. Fossils like this are technically trace/body fossils preserved within sedimentary rock layers like the Hell Creek Formation.
Field identification & locations
Identified by the distinct therapod skull shape, large fenestrae (holes in skull), and serrated teeth. Found primarily in North American badlands.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary