Lighting - Halogens Vs Daylight Florescent Bulbs?

I use halogens, only because they come small enough (MR16) for me to get them closest to vertical above the coin. Daylight bulbs mimic best the conditions of natural sunlight, but with white balance correction the color temperature of what you're shining on the coin really doesn't matter.

As a rule of thumb, 50-100w total is more than enough for any coin. I'm more likely to use a single 50w on a lustrous coin than a dull one, but all coins are different.

With that said, the very best coin photographer I know uses a single 60w incandescent and creates gorgeous lifelike pictures.