Manganese 25 Mn 54.93805	Large rock of Manganese.

Properties

Symbol	Name	Atomic Number	Atomic Weight	Group Number
Mn	Manganese	25	54.93805	7

Description

Standard State: solid at 298 K
Color: silvery metallic

Manganese was recognized by Scheele, Bergman and others as an element and isolated by Gahn in 1774 by reduction of the dioxide with carbon. Manganese minerals are widely distributed; oxides, silicates, and carbonates are the most common.  The discovery of large quantities of manganese nodules on the floor of the oceans holds promise as a source of manganese.  It resembles iron but is harder and very brittle.  In steel, manganese improves the rolling and forging qualities, strength, toughness, stiffness, wear resistance, hardness, and hardening ability.  It is an important trace element and may be essential for utilization of vitamin B1.