Characteristics of Shell:

Chemical Name: Calcium carbonate, aragonite

Formula: CaCO3

Colors: White, pink, silver, cream, brown, green, blue, black, yellow

Structure: Amorphous

Hardness: 3-4

Specific Gravity: 2.60-2.78

Refractive Index: 1.52-1.66

Lustre: Pearly

Locations: Worldwide

What is Shell? 

Seashells are in the exoskeletons of molluscs, composed primarily of a mineral secretion, as opposed to living cells. Seashells have a long history of use in body ornamentation, and the cowrie, in particular, in currency. Tortoiseshell is of different substance – the scutes (plate) of the shell used decoratively are of keratin, the protein that also forms fingernails and hair. Tortoiseshell is actually from the Hawsbill turtle, which is now protected. It is a natural plastic, meaning it can be heated and molded into new shapes.