At https://phys.org/print435394061.html … international study identifies the process of rock formation by meteor strikes (or nuclear blasts). Nice headline but coesite is a polymath of silica that only forms under extremely high pressure -ten thousand times greated than normal atmospheric pressure. The presence of coesite indicates either that the material has pushed up through earth's crust from the Mantle – or that a comet or meteor struck the site. Lightning bolts as perceived by EU people are not mentioned. Coesite can also be formed by modern nuclear explosions – which involve great heat and blast.
The mechanism by which silica is transformed into coesite is poorly understood but coesite is a silicon dioxide. Its chemical composition is similar to quartz. High temperature destructures the crystal lattice of quartz and compresses the silicon and oxygen atoms. The result if his high density glass. One is left wondering if the silica that formed into flint and chert, often found in cracks and cavities in the chalk formation, even enveloping sponges and other sea floor creatures, may not have originated from the Upper Mantle (rich in silica and water). Did it upwell into the sea floor from ocean vents?
The discovery of coesite at Chicxulub is significant as this geological formation is thought to be the site of a comet or asteroid impact. The circular crater has a diameter of 180km and is buried deep below the surface of Yucatan.