Having multiple black cars in the garage I've done a bit of "triage" to the inevitable scrape and stone chip.
If you are wanting to do something yourself that's actually pretty easy.
First realize only you can see the stone chip ..... it's not visible to anyone else from more than 10 feet away.
Second, "do no harm" ..... don't do anything crazy like rattle canning with spray paint!
Google up some Black Sapphire Metallic touch up paint (Amazon or a BMW supplier) and throw away the brush that comes with. Use a toothpick or an artist brush to fill the hole and it will disappear.
Our cars are not going to rust in Atlanta unless you spill a "con sal" margarita on the chip spot!
"sometimes you're the windshield .... sometimes you're the bug"
2014 328i Mojave Metallic
2009 328i Black Sapphire Metallic
2007 328i Black Sapphire Metallic
2007 Honda S2000 Berlina Black
(Hey Jim... am I diversified?)