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jnmczurich writes:

Ries Belemnites from the meteorite impact crater Nördlinger Ries/Germany

Belemnites are an extinct primeval group of squid (Pic 1) whose rostra have been preserved in fossil form. The belemnites shown here, originally embedded in limestone, are from the Jurassic period and were broken up into many small fragments and slices by the impact of a huge meteorite on the Swabian Jura around 15 million years ago (Pics 2-4) (Photo credit Pic 2: Spektrum der Wissenschaft, issue 01/1981). This fracturing was caused by the shock waves that ran through the bedrock as the crater was formed. In the millions of years that followed, the fractures were sealed again by crystallizing minerals.

Pics 5-7: Side views of so called "Ries Belemnites".

Today you can find this impressive fossil evidence of the gigantic meteorite impact only in very few places of the Nördlinger Ries, e.g. in Ronheim quarry or Heerhof quarry.

Pics 8-9: thin sections of two different Ries Belemnites. There is almost no color to see in polarized light.

Belemnites broken and shifted in steps, as shown in these pictures, are only found at the meteorite impact crater Nördlinger Ries.

Pics 10-12: The rare fragment of a very large Ries Belemnite is about 85 mm long and the steps are shifted from 2 to 13 mm, depending on the rotation of the Belemnite fragment.

An interesting mythological interpretation of the Belemnites can be found at the following link (written by Jack Wilkin. Pic 1 was taken from his publication).

Stratigraphy, Sedimentology and Palaeontology | Belemnites in Mythology - From Thunderstorms to Fertility Symbols. (egu.eu)

Excerpt from it:

Belemnites take their name from the Greek word belemnon meaning dart or javelin. The term rostrum comes from the name of the battering rams found at the front of ancient Roman and Greek ships in Antiquity. The fossilised rostra were widely believed to have been flung down as darts from heaven during thunderstorms (thunderbolts). Such beliefs were widespread also during the Medieval Period in Europe with houses in parts of southern Germany where rostra were placed under the roof tiles to help prevent lightning strikes. Similar stories are also found in the Netherlands with these "donderstenen" or "Donar’s stones" (Donar being the Old High German word for Thor) were kept in the roof to protect houses from lighting strikes.