I poked my head into my attic crawlspace today to see what the insulation situation was.

The house was built in 1909.

There is a little bit (barely covering the lathe) of black rock bits and old plaster lying in between the joists.

Is this vermiculite? Or is it something else? Sorry for the low quality photos--this stuff is definitely black and it looks like coal bits--shiny black.

If it is vermiculite, can I simply cover it with unfaced fiberglass insulation?