Ammonites (ammonis cornus,
or horns of [the Egyptian horn bearing God] Ammon,
are an extinct branch of the cephalopod class (Cephalopoda) within
the mollusk Phylum (mollusca).
These marine animals, along
with all Ammonoids, may no longer be found in our oceans today,
but they were once a ubiquitous life form throughout the oceans
as far back as 400 million years ago until the mass die-off during
65 million years ago at the end of the Cretaceous Period.
Ranging from a mere few
centimeters in diameter to a whopping 4 and a half feet, Ammonites
can be easily distinguished from their distant cousin, the smooth-bodied
modern Nautilus in the curved saddles (peaks) and lobes (valleys)
separating its individual chambers.
Although they are typically
known for their coiled shape, some orders of Ammonites actually
had straight or even helix-shaped bodies. Ammonites probably
fed on smaller forms of sea life and, in turn, were probably
food for larger fishes and reptiles that hunted in the ancient
Ammonites, when preserved
under the right conditions, can be classified not only in the
fossil world but may be considered to be ammoLITES, making them
only fossils which have earned a place within the gem and mineral
This can occur only when
the shell remains of an ammonite would fall to the ocean floor.
Here, due to the anaerobic nature of the sediment and other factors,
minerals surrounding the shell would soon create a protective
barrier around its surface.
If the conditions were
just right, as can be found in Canada and Madagascar, the top
layers of the fossil had been stripped off, leaving layers which
display an opalescence when polished.
Due to the brilliant colors
they display, ammolites have become some of the most sought after
fossil cum gems in recent years.
Many specimens display
luminescent flashes of red and green and have become a jewelry
of choice for individuals who are drawn to colors found in dichromatic
glass, yet want to wear a true piece of natural art.