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Abalone is a common name for any of a group of small to very large sea snails, marine gastropod molluscs in the family Haliotidae.

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Ammolite is an opal-like organic gemstone found primarily along the eastern slopes of the Rocky Mountains of North America. It is made of the fossilized shells of ammonites, which in turn are composed primarily of aragonite, the same mineral contained in nacre, with a microstructure inherited from the shell. It is one of few biogenic gemstones; others include amber and pearl.1 In 1981, ammolite was given official gemstone status by the World Jewellery Confederation (CIBJO), the same year commercial mining of ammolite began. It was designated the official gemstone of the City of Lethbridge, Alberta in 2007.

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Copal is a name given to tree resin, particularly the aromatic resins from the copal tree Protium copal (Burseraceae) used by the cultures of pre-Columbian Mesoamerica as ceremonially burned incense and for other purposes. More generally, the term copal describes resinous substances in an intermediate stage of polymerization and hardening between "gummier" resins and amber.

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Jet is a type of lignite, the lowest rank of coal, and is a gemstone. Unlike many gemstones, jet is not a mineral, but is rather a mineraloid. It is derived from wood that has changed under extreme pressure.

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Kauri gum is a fossilised resin extracted from kauri trees, which is made into crafts such as jewellery. Kauri forests once covered much of the North Island of New Zealand, before Māori and European settlers caused deforestation, causing several areas to revert to sand dunes, scrubs, and swamps. Even afterward, ancient kauri fields continued to provide a source for the gum and the remaining forests.

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Oltu stone is a kind of jet found in the region around Oltu town within Erzurum Province, eastern Turkey. The organic substance is used as semi-precious gemstone in manufacturing jewellery.

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The operculum, meaning little lid, is a corneous or calcareous anatomical structure like a trapdoor which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc.

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Precious coral, or red coral, the common name given to a genus of marine corals, Corallium. The distinguishing characteristic of precious corals is their durable and intensely colored red or pink-orange skeleton, which is used for making jewelry.