The difference between Heartless and Stony

When used as adjectives, heartless means without a heart, whereas stony means as hard as stone.

check bellow for the other definitions of Heartless and Stony

Heartless as an adjective:

Without a heart; specifically, without feeling, emotion, or concern for others; uncaring.

Examples:

"His heartless actions and cold manner left her saddened and feeling alone."
Heartless as an adjective (dated):

Lacking courage or enthusiasm.

Stony as an adjective:

As hard as stone.
Stony as an adjective:

Containing or made up of stones.

Examples:

"a stony path"
Stony as an adjective (figuratively):

Of a person, lacking warmth and emotion.
Stony as an adjective (figuratively):

Of an action such as a look, showing no warmth of emotion.

Examples:

"She gave him a stony reception."
Stony as an adjective (UK, _, &, _, Australian, slang):

without any money.