carry, take, etc. coals to Newcastle

idiomPart ofcoal

carry, take, etc. coals to Newcastle — idiom

1. To bring something to a place where it is already very common or plentiful.

1.idiom
Definition

To bring something to a place where it is already very common or plentiful.

Example

Bringing sandwiches to the picnic was like carrying coals to Newcastle.

Selling ice to people in Alaska is taking coals to Newcastle, isn't it?