Coal slag on aluminum

I have various aluminum engine parts I would like to clean up. Maybe even paint. I have access to a blasting cabinet with TCC Black Blast (coal slag) in it. I can't find any information on whether or not this is good or bad on aluminum. I didn't really want to replace the media. Anyone know for sure? TIA.

baking soda works well imo.

That coal slag is great for etching concrete, but I suspect it'll tear the hell outs aluminum. I would suggest a test piece of aluminum first, that way if it is too aggressive you won't damage a good bike part

Use the coal slag on the parts that you will paint, but not the other stuff. It definitely imparts a texture to the surface that would be very difficult to polish off. The texture does give plenty of tooth for paint adhesion however.

Rats. Glad I asked. Thanks Guys.