6-459: Eozoön canadense (literally, "dawn animal of Canada") is a pseudofossil . John William Dawson described the banded structures of coarsely crystalline calcite and serpentine as a gigantic Foraminifera , which was thought to be the oldest known fossil ( Dawson 1865 ). It was found in Precambrian metamorphosed limestone of Canada , at Côte St. Pierre near Grenville ( Quebec ) in 1863. It
12-459: Is a stub . You can help Misplaced Pages by expanding it . This metamorphic rock -related article is a stub . You can help Misplaced Pages by expanding it . Pseudofossil Pseudofossils are inorganic objects, markings, or impressions that might be mistaken for fossils . Pseudofossils may be misleading, as some types of mineral deposits can mimic lifeforms by forming what appear to be highly detailed or organized structures. One common example
18-480: Is a complex laminated form of interlayered calcite and serpentine originally found in Precambrian metamorphosed limestones (marbles). It was at first thought to be the remains of a giant fossil protozoan (Dawson, 1865), then by far the oldest fossil known. Similar structures were subsequently found in metamorphosed limestone blocks ejected during an eruption of Mount Vesuvius . It was clear that high-temperature physical and chemical processes were responsible for
24-870: Is when manganese oxides crystallize with a characteristic tree-like or dendritic pattern along a rock fracture. The formation of frost dendrites on a window is another common example of this crystal growth. Concretions are sometimes thought to be fossils, and occasionally one contains a fossil, but are generally not fossils themselves. Chert or flint nodules in limestone can often take forms that resemble fossils. Pyrite disks or spindles are sometimes mistaken for fossils of sand dollars or other forms (see marcasite ). Cracks, bumps, gas bubbles, and such can be difficult to distinguish from true fossils. Specimens that cannot be attributed with certainty to either fossils or pseudofossils are treated as dubiofossils . Debates on whether specific forms are pseudo or true fossils can be lengthy and difficult. For example, Eozoön
30-449: The formation of Eozoön in the carbonate rock (O'Brien, 1970). The debate over the interpretation of Eozoon was a significant episode in the history of paleontology (Adelman, 2007). Chemical gardens can produce branching microtubuli of 2-10 μm in diameter and can resemble very closely the shapes of fossilized primitive fungi or microorganisms . It has been proposed that ancient, Precambrian , structures that have been identified as
36-597: Was later found in several other localities. Dawson called it "one of the brightest gems in the scientific crown of the Geological Survey of Canada ". In 1894, it was shown that the place where it was found was associated with metamorphism ( O'Brien 1970 ; Adelman 2007 ). Similar Eozoön structures were subsequently found in metamorphosed limestone blocks erupted from Mount Vesuvius , where high-temperature physical and chemical processes were responsible for their formation ( O'Brien 1970 ). This paleontology article
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