This tool was in a box lot and I'm not sure what it does.  I figure it should have a wood handle.  Looks like you place it on something and pound on the end with a hammer to mark it.

I think you are right the other tool that is similar is for  horse dentist, file teeth down. The file teeth are  like a lead / vixen file. Had one years ago thought it was for lead work.

Or, if not a horse dentist, a specialized riffler for some application.

Rifflers, which come in both file (this picture) and rasp forms:

Gunsmiths's or plane maker's float?

The leather working related tool you are thinking of is called a shoe peg float.  There are a few different kinds of teeth.  Most of the shoe peg floats or rasp have a higher angle on the shank.  They all had wooden handles like a file.  They were used to file off the wooden shoe pegs that on the inside of the boot or shoe that were used instead of nails on mariner's or other waterproof footwear.  After filing them down, the insole would be put in.  There is a very good write up in Salaman's Dictionary of Leather-Working Tools book.

Because of the angle, I will go with a horse tooth file or rasp.

Also, the horse floats tend to be finer and the shoe peg rasp tend to be coarser, based on the ones that I have had.

Well, it now has a fine handle from my handle hoard.  I now agree it is not a leather tool. An update on the working end follows.  In looking closely I found the ( i will call it a pad or working end) is divided into two sections, about evenly.  The front section has the points leaning forward to cut going forward and the rear portion has the points pointing back to cut when pulling back.  Does this change any ideas??

Based on your description, it seems like the tool you discovered is a leather stamping tool. It's used to make marks or impressions on leather by placing it on the surface and tapping it with a hammer. The wooden handle you mentioned is indeed used to hold the tool while you apply pressure with the hammer.
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