Unknown rock.

It's important to differentiate between a magnet sticking to it, or a piece of iron sticking to it. If a magnet sticks to it then it has iron in it, but if a piece of Iron sticks to it, then it's not only got Iron in it, but it's also magnetic.

You obviously have something with Iron in it. Where was it found, in a natural area or in a quarry or at a construction site?

The next level of information would require a specific gravity on the object. You would need to weigh it accurately and then submerge it in water and see how much water it displaces. Then calculate a specific gravity.

You could also scrape it a bit to see how hard it is, and finally, if possible, cross-section it to see what's inside.

Farmerman will have more specific recommendations once he finds this thread.

Here is an embed of your image:

looks kind of like an "iron gneiss" that's been rolled in a stream.
Its not a meteorite (Im fairly sure but not 100%).
Ros idea of cutting a slice and giving it to a geology department at U for an energy dispersive xray would give a reading of all the components.
Does the magnet attract more strongly at some spots than at others on the surface of the rock? (Use a thin magnet that is mounted on the
end of a rod)
The Sudbury mining district and the Upper Peninsula have lots of these gneissic banded magnetites that get tumbled in streams quite readily.

It almost looks like a large Taconite pellet which is composed of an iron and silica powder that is mixed and compressed into small pellets which are fed into furnaces for smelting . This looks like a big version of that.

Heres an example of an iron gneiss nodule surrounded by a "vein" of white stromatolites.precambrian
This ones from the U of Nebraska's geology photo archive

As an erstwhile rockhound Ros I'd weep

different crystal structures of metals can give very interesting prismatic patterns in cross sectioning and polishing. A meteorite, fro example, because of the two speies of iron and nickel minerals, develop these interlacing prisms called Widdmenstaten patterns. These define a nickel-iron meteorite.
Anyway we don't have to cut the thing right down the middle, one can take a small section from an end . The x-ray testing will reveal pretty much the same stuff

Clearly Man your background far exceeds mine, I collected the ones I found pretty on the outside though I did some cutting-polishing

…often out of laziness coating with urethane etc instead of polishing, an awful mistake as I've learned in my old age

what youre looking at in a meteorite is the adjacent plotzing of taenite and kamacite. One has a Ni ( >30%) and iron of (,50%) and the other has an iron of (>70%) and Ni(,20%). The taenite (higher Ni has a face centered cubic crystal and the Kqmacite has an end centered cubic crustal. SO they will give off really sharp edged Widdmenstatens which are really neat looking.
You should polish to 2000 grit and then Al rouge buff.
(I always send any samples out to get done. I have no patience in doing thin sections or any kind of polishing any more. It a skill Ive never acquired and I usually need mineral results reported within 3 or 4 days after discovering them in the field.