I found this in a pile of old tools. It's some kind of steel-brass Damascus. I can't figure out if it's a machinist thing, or an actual piece of Damascus. 

Is it the same on the other side?

Brass and steel aren't "damascus" though you can combine the two in a similar diffusion welding technique, Mokume Gane.

Actually brass and steel bond easily. (see brazing) No idea what the purpose of that might have been but it'd be easy to make, very easy, easier than a mokume gane billet.

Frosty The Lucky.

Yes, it's a "Machinist's Tool".

It's a laminated block, used in conjunction with a Magnetic Chuck, ... most likely on a Surface Grinder.

The brass laminations create a separate magnetic field in each steel lamination, ... causing the block to hold onto a Magnetic Chuck much more securely than a solid steel block of the same size.

It's all the way through, what I wanna know is, can I forge it? I bet it would make something awesome, but I don't want to risk delamination. 

It reminds me of the edge of a quarter like the ones made after '64  that are pressed metal instead of silver.

Sure you can forge it---it will fall apart as brass is a liquid at a good forging temp for steel...and very iffy slightly below that temp.  You *might* be able to cold work it though the annealing passes may cause problems depending on the alloy used.

Hmm I don't want to completly destroy it

Sell it, magnetic parallels are sought after. I have a set for my surface grinder. 

Is it something that could be of use to me? I hate to sell a tool only to find that I needed it later on. 

Depends on how old you are, and if you ever get into bonified machine shop work. Put it on a shelf and admire it, for it is a nice piece of technology.

Hmmm..... I have a mag chuck......

On second thought, I think it's poisonous - perhaps you might send it to me for proper disposal .

Robert Taylor

Lol