Ginkgo Fossil Leaf
Image: <a href="//commons.wikimedia.org/wiki/User:Kevmin" title="User:Kevmin">Kevmin</a> (CC BY-SA 3.0)
Mineral NameGinkgo Fossil Leaf
Chemical FormulaPrimarily carbonaceous material replaced by various minerals (e.g., SiO2, CaCO3, FeS2) within a sedimentary matrix.
Mohs Hardness2
Crystal Systemamorphous
Streak Colorbrown to black (of fossil); varies with matrix
CleavageNone (fossil); matrix may exhibit parting
Fractureuneven/conchoidal
Specific Gravity2
Colorsdark brown, black, yellowish-tan, light tan
Transparencyopaque
Type LocalityKlondike Mountain Formation, Republic, Ferry County, Washington, USA
Mineral GroupFossil (Biogenic)
Usesscientific study, educational displays, collector's item
Associated Mineralsclay minerals, quartz, calcite, other plant and insect fossils
Rarityuncommon
Description
A well-preserved fossilized Ginkgo biloba leaf, approximately 70mm wide, displaying dark brown to black venation and a yellowish-tan lamina, embedded in a light tan sedimentary matrix.
Geological Context
This fossil dates to the Eocene (Ypresian, 49 million years old) and originates from the Klondike Mountain Formation, known for its exceptionally preserved flora and fauna from an ancient lake environment.
