Weird cut/graze?

[srmichae]

N.b. Got a vet appointment booked on the 30th

Pup has these weird grazes on his leg. The fresh one looks like a normal graze but the other one has little black bits on it which I'm worried about.

Any ideas?

https://postimg.cc/QVWJJLpV
https://postimg.cc/gX1qb4PY