Need help identifying please.

[oh_joy52 0]

I was at Whiskey Bridge near College Station, Texas digging along the lower bank of the Brazos River. I had dug about a foot down and found this small round rock. When I got it home I used my jewler's loop to look at it more closely. I found tiny indentions that looks like tiny creatures. Can someone identify what these are? Also the black one is rough and smells like metal but didn't pass the metal test. This was in the same hole.

Thanks 
Joy

[d_day 350]

Not sure about the first one. Second appears to be a concretion.

[oh_joy52 0]

That is helpful. Thank you. There are what looks like minerals growing on it as well. 

[chrisski 856]

In the first pic, the green staining appears to be a copper ore.

My guess is the white stains is salts that come out of The water when it evaporates and this happens time and time again.  I see that Salt staining at any reservoir I go to in the Southwest when its below the high water mark, which is all the time.  I know its called salts, but that really means any mineral left in water when it evaporates.

You can put a drop of vinegar on each one and see if it fizzes.

[oh_joy52 0]

Ok thank you!