The initial site, discovered in 1975 by Klaus Müller and his assistants, exceptionally preserves soft-bodied organisms, and their larvae, who are preserved uncompacted in three dimensions. The fossils are phosphatized and silicified, thus the delicate chitinous cuticle and soft parts are not affected by acids, which act upon the limestone nodules within which the fossils have survived. Acids dissolve the limestone, revealing the microfossils in a recovery process called "acid etching".
The initial site, discovered in 1975 by Klaus Müller and his team, is exceptionally well-preserved, preserving soft-bodied organisms and their larvae in three dimensions. The fossils are phosphatized and silicified, protecting the delicate chitinous cuticles and soft parts from acids that would otherwise dissolve the limestone nodules they're encased in. Acid etching is then used to reveal the microfossils.