Description: If you are making more than one purchase, please read the note following the red text below. Hand/display specimen of light tan lacustrine limestone from the middle member of the Eocene Green River Formation, Duchesne County, Utah This light tan silty limestone is interbedded with shales in the Eocene Green River Formation in northeastern Utah. A series of extensive inland lakes covered the region during the Eocene. The Laramide Orogeny 88-40 million years ago, created the uplifts that surround the Uinta Basin. The Green River Formation in this basin is a sequence of carbonate and organic-rich mudrocks of lacustrine origin and fluvially-derived sandstones. Famous for its fossil flora and fauna, the Green River contains huge reserves of oil shale. Limestones are primarily biogenic in origin, being composed of the protective shells of small organisms that extract calcium carbonate from seawater to build their shells. There is a constant rain of microscopic shells and other calcareous parts onto the sea floor, which when accumulated and consolidated becomes limestone. Chalk is a form of limestone composed entirely of the minute calcium carbonate shells of coccolthophores, a unicellular phytoplankton. Coquina is a form composed of shells and shell fragments, only partly consolidated. When a limestone contains clay, it grades towards shale and is called an argillaceous limestone. Because the composition of limestone is calcium carbonate, a limestone will strongly effervesce with dilute hydrochloric acid. This limestone was collected at an elevation of 8,900 feet at Indian Creek Pass on US Highway 191, between Helper and Duchesne, Utah, on the West Tavaputs Plateau of the Uinta Basin and is a good contrast with the more typical gray limestones. Students should understand that limestone is not always gray, and that it can vary in color. These specimens fit in a 3.75" x 5" unit tray. Select a specimen:You can select a specimen by telling us what is in front of it - a black mechanical pencil, a silver and black pen, a silver and blue pen, or one of those plus some number of coins, or you can let us make the selection. Making multiple purchases?Just add items to your cart. When finished shopping, click on “request total” at upper right in the Shopping Cart window. Do not proceed to checkout. We will send an eBay invoice with the correct combined shipping. The combined shipping will often be less than eBay shows. Please wait for that invoice before paying. There is no obligation to purchase. You can decide after seeing what shipping will cost.Shipping: Priority Mail, which varies by weight and zip code. We can ship for less than eBay will charge, and will refund the overpayment as soon as the box is packed. International customers: We sell and ship internationally. If eBay’s page does not let you enter your country name to determine the shipping cost for something you are interested in, please contact us. We can tell you what the shipping would cost and how to make the purchase. You can then decide if you wish to complete the transaction. Use the Contact Seller link in the Seller Information box on the right side of this page. Pay securely with your debit or credit card through PayPal! You do not need a Pay Pal account to do this. Yes, we do combine shipping! Click on "Request total" in the shopping cart for a no-obligation invoice to see the total with shipping.
Price: 10.45 USD
Location: Olancha, California
End Time: 2024-09-25T21:52:32.000Z
Shipping Cost: N/A USD
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Return shipping will be paid by: Seller
All returns accepted: Returns Accepted
Item must be returned within: 30 Days
Refund will be given as: Money Back
