So I found this rock..?

Question

So I work at a beach in Michigan, and today I was combing the beach and I found a jet black rock. It was perfectly smooth except for a very small portion. It is approximately 1 inch by 1.5 inches, .5 inches thick.

Interestingly, I found this about 100 yards from water, not near it

I only picked the rock up because this beach has nothing but sand on it, and finding any rock in general is something uncommon, let alone a black rock such as this one.

When I came home, something possessed me to take a magnet to it and see what happened (because the rock feels bizarre, I can't really explain it, maybe just because it is so smooth). So of course the magnet stuck to the rock fairly well, not as good as sticking the magnet on a refrigerator though, but there was still enough attraction that the magnet stuck.

Of course I would guess there must be some iron in this rock, but I don't know anything about geology so I was hoping someone with a bit more knowledge could help me.

Thanks in advance!

Answer 1

It seems to be Hematite.  I found images that fit your description perfectly.  The closest was called a Hematite palm stone and the other was called Hematite tumbled.

Answer 2

I would think magnetite, myself.  Hematite is not very magnetic.  It may be from an ore shipment, or it may be from a local iron formation (magnetite-bearing sedimentary rocks).

It may not even be dominantly magnetite, but sufficiently endowed with magnetite to become attractive to a magnet.

Really impossible to identify by the info given.  Magnetite in the rock is the most probable cause for the magnetic attraction, pretty well determinative.  Beyond that, difficult to say without actually seeing the rock.

Answer 3

probobly a lava rock.

Answer 4

I'm with Kay, I think it's hematite too.  If it were magnetite, the magnet should have stuck better too it. Actually, it must be a strong magnet if it's hematite, because the magnetism of hematite is usually quite weak.  Another possibility is ilmenite.