Jelinite

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Jelinite (also Kansas amber ) is the name for Cretaceous amber from the Ellsworth County area ( Kansas ). The name was given in honor of the collector and discoverer of the site of this amber deposit, George Jelinek. The name Kansasite originally proposed by Buddhue (1938) is no longer used today.

Find area and geology

George Jelinek found the amber in 1937/1938 in an outcrop at the base of the protruding shale and sandstone cliff of the Smoky Hill River not far from Ellsworth County. The site is now below the water level of the Kanopolis reservoir, which was created in 1948, and is therefore no longer accessible. Geological investigations carried out close to the time it was first found indicate that the amber was in the Cretaceous period (around 100 million years). The sediment in which the amber was found is very likely to be layers of the Kiowa shale ( Albium or Cenomanium ).

Features of the Jelinit

Jelinite is brittle and has a shell-like break. The finds are mostly small, flattened spheres. The Mohs hardness is between 2.5 and 3. The specific weight is 1.05 to 1.06. The surface becomes soft by drizzling with ether and dissolves to a small extent. The resin does not react to nitric acid , acetic acid , dilute potassium hydroxide , 28% ammonium hydroxide , or acetone . Melted jelinite makes a brown oil. Amber is not suitable for making jewelry.

Botanical origin

The IR spectrum of Jelinit similar to the spectra of several other Cretaceous and Tertiary amber deposits (u. A. Chemawinit , Ambrit , Ajkait , Walchowit ). These spectra show a high degree of agreement with those of the resin of the recent Agathis australis . This in turn points to a botanical origin of the jelinite in a tree from the Araucariaceae family, which no longer occurs in the northern hemisphere .

Organic inclusions

In addition to pollen from conifers , various aquatic microorganisms were identified that indicate a swamp-dwelling resin producer.

literature

  • JD Buddhue: Some new carbon minerals - kansasite described. In: The Mineralogist 6 (1), 1938. pp. 7-8, 20-21.
  • RL Langenheim et al .: Age and occurrence of the fossil resins bacalite, kansasite, and jelinite. In: Journal of Paleontology , 1965. pp. 283-287.
  • BM Wagoner: Bacteria and protists from Middle Cretaceous amber of Ellsworth County, Kansas. In: PaleoBios 17 (1), 1996. pp. 20-26.

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