Took me a minute. I thought this was about Blackrock.
They are closely related and were co-developed, per my understanding. Rumors claim the names come from the muslim meteor rock that’s worshipped at Mecca.
Blackrock vs Blackstone
Blackstone’s business is in real estate, private equity, hedge fund solutions, and credit and insurance. On the other hand, Blackrock’s business is in equity, fixed income, multi-asset, alternatives, cash management, and advisory.