Every one of my Alembic guitars has a mahogany core. Would someone please be so kind as to tell me comparatively what different tonal properties I could expect from a guitar with a vermillion core.

This page describes the tonal qualities of the various body woods...
 
http://alembicguitars.net/info/wood_body.html

You might want to look at the Body woods page at the main site. Note that the example they give is a Skylark guitar, so it's not only for basses.

Jonathan:
 
Woody has a vermillion core.   I was looking for something a little warmer than the standard purpleheart.   I like it.
 
Bill, tgo

I gave serious thought to vermilion/padauk as a core wood, as well as neck laminates when planning my custom. There was a time when I couldn't decide between vermilion and birdseye maple for the top and back too. Another sleepless night I pondered inverting the wood for a solid maple core with vermilion top and back. It's awfully pretty wood, especially after it ages a few years.