Black dots/spec on my clone rockwool cubes!

What could these black specs be on my rockwool cubes. Possible the humidity was or is too high, and henceforth i have mold?
They have been under my makeshift humidity dome, i think it is too small i got another much larger one today, took the empty 300 mini candy cane container from work.
The cubes and the clones have been in place since Wednesday, i have been spraying them with Thrive Alive B1 like my sheet for my nuts says so.
Any info is appreciated.

show me pic it mite be lsf

Little tiny black dots in the rockwool, look almost shinny?

I think its rock dude!!

lol yea i thing its rock material almost looks like small peices of coal right? i use grodan cubes and as i water them with time i see the same thing nothing to worry about in my book as i have seen this and it has never hindered my crop.

thank god for this post i thought i had a bug infestation.

im getting the same thing wth is this shit?