Ammonite

Slowing down decay

Called Eoderoceras, this is probably the largest ammonite preserved in iron pyrites that can be picked off the beach in a perfect state. There is a down-side though – pyrite ammonites can decay because the iron sulphide is unstable on contact with oxygen in the air. The best solution is to keep the specimens somewhere dry to slow the process down.

Find out more about ammonites on the molluscs pages.

Common name

Ammonite

Scientific name

Eoderoceras armatum

Type

Molluscs > Cephalopods


Strata

Black Ven Marls

Time period

Lower Jurassic

Age

c. 201-174 million years

Where found

Stonebarrow, Charmouth

Found by

unknown

Museum

Bridport Museum

Accession number

BRPMG 1111