There's 3 at the 3 barges. Mine it that black plastic coated mushroom with 3 small flange looking design with a short piece of yellow nylon 3/8" rope. This past Monday or Tuesday, a guy cut his anchor rope bc he couldn't get it freed. Not sure what type it is, but about 50' of anchor rope is attached. Then weekend b4 last, a guy cut his too at the barges, rope attached. It's like the picture above ^^^. So those 2 should be easy to spot if diving, just follow the rope.
Haven't been to barges since I found that last anchor. I do have some 8 and 13 danforth types $10 and $15 chain is $1 a foot free shackles and bring anchor line I'll splice it free to chain. Will be here this evening. Pm me I answer when available.