{"product_id":"one-calymene-trilobite-2-5-x-1-75","title":"One Calymene Trilobite - 2.5\" x 1.75\"","description":"\u003cspan\u003eFossils of this species have been found in the Silurian sediments of the United States. Most specimens have been found in New York and Oklahoma. Trilobites were a very diverse group of extinct marine arthropods. They first appeared in the fossil record in the Early Cambrian (521 million years ago) and went extinct during the Permian mass extinction (250 million years ago). They were one of the most successful of the early animals on our planet with over 25k described species, filling nearly every evolutionary niche. Due in large part to a hard exoskeleton (shell), they left a excellent fossil record.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eWhile digging for fossils, real limestone matrix fossils will have been split and broken up to see if a fossil is present in the limestone. This is an unavoidable break of the trilobite prior to preparation. Afterwards the pieces are carefully glues back together and the fossil extraction can proceed. When the matrix is carefully removed with professional tools under a microscope, the fossil will keep the scars of the original fractures and the better the preparation, the less break tracks remains.\u003c\/span\u003e","brand":"Store for Knowledge","offers":[{"title":"Default Title","offer_id":48376691916957,"sku":"Vil-CalymeneTrilobite","price":3.25,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0764\/4931\/7021\/files\/Trilobites.jpg?v=1780621820","url":"https:\/\/storeforknowledge.com\/products\/one-calymene-trilobite-2-5-x-1-75","provider":"Store for Knowledge","version":"1.0","type":"link"}