Skillful preparation Whenever is see beautiful specimens like these, or read some interesting museum
Skillful preparationWhenever is see beautiful specimens like these, or read some interesting museum or university based research on dinosaurs, I am very aware of the many hours of unsung work that has been put in by a rather unacknowledged profession: fossil preparators. Whether Moroccan families working on the trilobites that grace many a private or museum collection, or skilled technicians working in the unlit dungeon basements of Earth Science faculties in universities or museums put hundreds of hours into uncovering specimens a millimetre at a time from the protective coating of solid rock that has entombed them for millions of years.Obviously some rocks are much tougher to chip away than others, but the work takes anything from weeks to years per specimen. Others are incredibly fragile mudstones for example, and require a great subtlety of touch to be able to release them from their stony tomb so that the researchers can cast their eager eyes on them without damage. They employ a variety of techniques.In the modern era many plaster encased chunks of dino bone are analysed first non invasively, using xray tomographic scanners to take layer by layer snapshots directly into a computer, creating a full 3d picture of the inside. This often determines the order in which things are done, with the most scientifically interesting coming first. This is only useable when sufficient contrast is available between bone and matrix, which in iron rich rocks can be a problem. It is also vital for fragile specimens, since much information can be extracted before the risk of damaging it during preparation is taken. These days the scanned bones can even be 3d printed without being extracted from the rock, which can save a lot of time.Sometimes the matrix is removed by mechanical means, such as dentists drills, and others by chemical ones, like dissolving limestone in weak acid from around a specimen (which takes a year or so). The latter can damage fossils, so is often used when mechanical prep would damage the piece. There are a wide panoply of tools for the former, and the most intense work is done under the microscope, on tiny bones from early mammals for example.Either way, the links below offer a glimpse into a little known corner vital to the geosciences as a whole and the aesthetic enjoyment of fossil collectors and museum visitors worldwide.LozImage credit: 1 Comura sp. Middle Devonian, Morocco: Sulla 55/ Houston Museum of Natural Science2 Walliserops trifurcatus Djebel Oufaten, Morocco: Kevin Walshhttp://preparation.paleo.amnh.org/http://s.si.edu/1JP0lgQ -- source link
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