Ginkgo Fossil Leaf
Image: <a rel="nofollow" class="external text" href="https://www.flickr.com/people/87547772@N00">Anders Sandberg</a> from Oxford, UK (CC BY 2.0)
Mineral NameGinkgo Fossil Leaf
Chemical FormulaVariable (often carbonaceous material, or replaced by SiO2, CaCO3, FeS2)
Mohs Hardness2.5
Crystal Systemamorphous
Lusterdull
Streak Colornot applicable
Cleavagenone (for the fossil itself)
Fractureuneven
Specific Gravity2.2
Colorslight beige, off-white, dark brown, black
Transparencyopaque
Type LocalityAlmont, North Dakota, USA
Mineral GroupFossil (Biogenic)
Usesscientific study, education, collector's item
Associated Mineralsclay minerals, quartz, feldspar, carbonaceous material
Rarityuncommon
Description
A well-preserved, fan-shaped fossil leaf of Ginkgo cranei, appearing light beige against a dark brown to black, irregularly shaped sedimentary rock matrix.
Geological Context
This fossil formed in the Late Paleocene, approximately 60 million years ago, likely through the rapid burial of a Ginkgo leaf in fine-grained sediments, leading to its preservation as a compression or impression fossil within a shale or mudstone matrix.
