Implies extreme resilience and determination in a person's character.

Mental Toughness

'Of steel' doesn't mean the person has actual steel in them, but symbolic strength.

Not Literal

The phrase can express someone's ability to handle emotional stress well.

Used to state that an object is actually made from steel, emphasizing its strength.

Suggests that the object is durable and strong, like the metal steel.

'Of steel' can convey an intense, piercing quality in a person's look or gaze.

Indicates someone is maintaining composure, not showing feelings openly.