Seashell in the context of Turbinate

A fossil (from Classical Latin fossilis, lit. 'obtained by digging') is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the fossil record. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of Tiktaalik in the arctic of Canada.

Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ages of rocks and the fossils they host.

Marine invertebrates are invertebrate animals that live in marine habitats, and make up most of the macroscopic life in the oceans. It is a polyphyletic blanket term that contains all marine animals except the marine vertebrates, including the non-vertebrate members of the phylum Chordata such as lancelets, sea squirts and salps. As the name suggests, marine invertebrates lack any mineralized axial endoskeleton, i.e. the vertebral column, and some have evolved a rigid shell, test or exoskeleton for protection and/or locomotion, while others rely on internal fluid pressure to support their bodies. Marine invertebrates have a large variety of body plans, and have been categorized into over 30 phyla.

Marine biogenic calcification is the production of calcium carbonate by organisms in the global ocean.

Marine biogenic calcification is the biologically mediated process by which marine organisms produce and deposit calcium carbonate minerals to form skeletal structures or hard tissues. This process is a fundamental aspect of the life cycle of some marine organisms, including corals, mollusks, foraminifera, certain types of plankton, and other calcifying marine invertebrates. The resulting structures, such as shells, skeletons, and coral reefs, function as protection, support, and shelter and create some of the most biodiverse habitats in the world. Marine biogenic calcifiers also play a key role in the biological carbon pump and the biogeochemical cycling of nutrients, alkalinity, and organic matter.

An artificial reef (AR) is a human-created freshwater or marine benthic structure.Typically built in areas with a generally featureless bottom to promote marine life, it may be intended to control erosion, protect coastal areas, block ship passage, block the use of trawling nets, support reef restoration, improve aquaculture, or enhance scuba diving and surfing. Early artificial reefs were built by the Persians and the Romans.

An opportunity artificial reef is built from objects that were intended for other purposes, such as sinking oil rigs (through the Rigs-to-Reefs program), scuttling ships, or by deploying rubble or construction debris. Shipwrecks may become artificial reefs when preserved on the seafloor. A conventional artificial reef uses materials such as concrete, which can be molded into specialized forms (e.g. reef balls). Green artificial reefs incorporate renewable and organic materials such as vegetable fibres and seashells to improve sustainability and reduce energy consumption, pollution, and greenhouse gas emissions. In some cases, artificial reefs have been developed as artworks.

Nacre (/ˈneɪkər/ NAY-kər, also /ˈnækrə/ NAK-rə), also known as mother-of-pearl, is an organic–inorganic composite material produced by some molluscs as an inner shell layer. It is also the material of which pearls are composed. It is strong, resilient, and iridescent.

Nacre is found in some of the most ancient lineages of bivalves, gastropods, and cephalopods. However, the inner layer in the great majority of mollusc shells is porcellaneous, not nacreous, and this usually results in a non-iridescent shine, or more rarely in non-nacreous iridescence such as flame structure as is found in conch pearls.

A button is a fastener that joins two pieces of fabric together by slipping through a loop or by sliding through a buttonhole.

In modern clothing and fashion design, buttons are commonly made of plastic but also may be made of metal, wood, or seashell. Buttons can also be used on containers such as wallets and bags. Buttons may be sewn onto garments and similar items exclusively for purposes of ornamentation. In the applied arts and craft, a button can be an example of folk art, studio craft, or even a miniature work of art. In archaeology, a button can be a significant artifact.

Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With over 1,700 living species, the Muricidae represent almost 10% of the Neogastropoda. Additionally, 1,200 fossil species have been recognized. Numerous subfamilies are recognized, although experts disagree about the subfamily divisions and the definitions of the genera.Many muricids have unusual shells which are considered attractive by shell collectors and by interior designers.

In biology, a test is the hard shell of some spherical aquatic animals and protists, notably sea urchins and microorganisms such as testate foraminiferans, radiolarians, and testate amoebae. The term is also applied to the covering of scale insects. The related Latin term testa is used for the outer layer of the hard seed coat of plant seeds.

Sand mining is the extraction of sand, mainly through an open pit (or sand pit) but sometimes mined from beaches and inland dunes or dredged from ocean and river beds. Sand is often used in manufacturing, for example as an abrasive or in concrete. It is also used on icy and snowy roads usually mixed with salt, to lower the melting point temperature, on the road surface. Sand can replace eroded coastline. Some uses require higher purity than others; for example sand used in concrete must be free of seashell fragments.

Sand mining presents opportunities to extract rutile, ilmenite, and zircon, which contain the industrially useful elements titanium and zirconium. Besides these minerals, beach sand may also contain garnet, leucoxene, sillimanite, and monazite.

Calcarenite is a type of limestone that is composed predominantly (more than 50%) of detrital (transported) sand-size (0.0625 to 2 mm in diameter), carbonate grains. The grains consist of sand-size grains of either corals, shells, ooids, intraclasts, pellets, fragments of older limestones and dolomites, other carbonate grains, or some combination of these. Calcarenite is the carbonate equivalent of a sandstone. The term calcarenite was originally proposed in 1903 by Grabau as a part of his calcilutite, calcarenite and calcirudite carbonate classification system based upon the size of the detrital grains composing a limestone. Calcarenites can accumulate in a wide variety of marine and non-marine environments. They can consist of grains of carbonate that have accumulated either as coastal sand dunes (eolianites), beaches, offshore bars and shoals, turbidites, or other depositional settings.

Wildlife trade refers to the exchange of products derived from non-domesticated animals or plants usually extracted from their natural environment or raised under controlled conditions. It can involve the trade of living or dead individuals, tissues such as skins, bones or meat, or other products. Legal wildlife trade is regulated by the United Nations' Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which currently has 184 member countries called Parties. Illegal wildlife trade is widespread and constitutes one of the major illegal economic activities, comparable to the traffic of drugs and weapons.

Wildlife trade is a serious conservation problem, has a negative effect on the viability of many wildlife populations and is one of the major threats to the survival of vertebrate species. The illegal wildlife trade has been linked to the emergence and spread of new infectious diseases in humans, including emergent viruses. Global initiatives like the United Nations Sustainable Development Goal 15 have a target to end the illegal supply of wildlife.