18.5" Polished Ammonite (Argonauticeras) Fossil - Giant Specimen!

This is a massive, 18.5" wide polished ammonite fossil (Argonauticeras besairiei), collected near Ambatolafia, Madagascar. It makes for a very impressive display on the included metal display stand.

You rarely get ammonites of this size out Madagascar. While it is incomplete on one side, this is to be expected on larger ammonites that will typically be found as partials or already fractured/fragmented within the rock. The rock from the display side has been meticulously prepped away and the ammonite has been polished.

Comes with a rebar display stand.

Ammonites were predatory cephalopod mollusks that resembled squids with spiral shells. They are more closely related to living octopuses, though their shells resemble that of nautilus species. True ammonites appeared in the fossil record about 240 million years ago during the Triassic Period. The last lineages disappeared 65 million years ago at the end of the Cretaceous.

What an ammonite would have looked like while alive.
What an ammonite would have looked like while alive.

Argonauticeras besairiei
Ambatolafia, Mahajanga Province, Madagascar
18.5" wide, 6.3" thick, 68.7 lbs
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