Crabs

Crabs can be found regularly in the London Clay formation, usually in small clay nodules however occasionly can be found in large septerian nodules. 

They can be recognised by their distictive black exoskeleton protruding from a baige nodule. 

However some of the crab species are extremely rare such as Sharnia Burnhamensis which is only known from a singular specimen. 

They are usually in stable condition after collecting from a site, However can sometimes have pyrite parts which will need stabilsing.