rennet tablets, and that which does not dissolve

[DougL]

So I take my rennet tablet and dissolve it in water before adding to my mix. I end up, ten minutes later, with a tan-colored liquid, and a fine sandy-like substance at the bottom. As in, stuff that does NOT dissolve. Can I assume that the rennet itself has dissolved, and the stuff left behind undissolved is some sort of binder for the tablet? Or did I just not wait long enough?