A searchable guide to the complete WordPress Icon Library (@wordpress/icons) package from Gutenberg.
import { Icon, headingLevel1 } from '@wordpress/icons';
<Icon icon={headingLevel1} />
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" aria-hidden="true" focusable="false"><path d="M17.6 7c-.6.9-1.5 1.7-2.6 2v1h2v7h2V7h-1.4zM11 11H7V7H5v10h2v-4h4v4h2V7h-2v4z"></path></svg>
headingLevel1 – WordPress Icon Library