The crown, that is, the glory of the wise man constitutes his wealth. He alone is truly rich even as he alone (compare Proverbs 14:18 note…

The crown of the wise is their riches.— They adorn and set off the wisdom of the wise, and bring it more to public attention; but …

The crown of the wise [is] their riches
Riches being used by them to increase and improve their knowledge and wisdom…

The riches of men of wisdom and piety enlarge their usefulness.