This area provides an explanation of how sites are located and how the fossils are extracted from them.
To locate a site the land has to be surveyed, which means the area is inspected to see if it might have sediments containing fossil remains. The survey is the first step in excavation, and authorization from the General Directorate of Cultural Heritage must always be requested, because all sites and fossils are protected.
When the excavation starts, the first step is to clean the area of any sterile sediments. Next, a grid of the plot is made to take the coordinates of the position of the pieces. Then the real excavation can begin, using the appropriate tools (brushes, chisels, hammers, scalpels, etc.). When a fossil is found, first the area round it must be reinforced before proceeding with its extraction. If the fossil is small and study, the sediment is wrapped in aluminium foil; if it is large and fragile, it is "mummified", which means it is wrapped in cardboard and polyurethane or plaster.
Finally, the piece is registered with a code and all the information is recorded in the field notebook, a basic palaeontological tool. This notebook becomes the first record of the fossil: the name of the site, the date and a description of the piece are recorded.