Fossil Pulalius vulgaris
Image: <a href="//commons.wikimedia.org/wiki/User:Kevmin" title="User:Kevmin">Kevmin</a> (CC BY-SA 3.0)
Mineral NameFossil Pulalius vulgaris
Chemical FormulaVariable (commonly CaCO3, SiO2, or iron oxides/sulfides)
Streak ColorDark brown to black
CleavageNone (for the fossil structure)
FractureIrregular to conchoidal (fossil), uneven (matrix)
Colorsdark brown, black, grayish-brown
TransparencyOpaque
Type LocalityUnspecified location in Washington, USA
Mineral GroupFossil (biogenic, permineralized)
Usesscientific study, education, collector's item
Associated Mineralsquartz, feldspar, clay minerals, calcite, silica, iron oxides
Rarityuncommon
Description
A well-preserved, dark brown to black fossil of a Pulalius vulgaris crab, embedded in a grayish-brown, surf-worn sedimentary cobble.
Geological Context
This fossil formed through the permineralization of a crab in a marine or coastal sedimentary environment, later incorporated into a surf-worn cobble.
