Vitamins

Step 1: Vitamin is also called cobalamin.
Step 2: It contains cobalt as the central metal ion.

Vitamin is also referred to as cobalamin, because it contains a metal ion (cobalt). This makes it the largest and most complex vitamin of all. The vitamin can only be synthesized by bacteria and therefore is mainly present in animal products. Two forms of Vitamin are used in the human body.

Vitamin B₁2 (cobalamin) contains cobalt at its core.