I have made a few of these Carving Mallets in the past – you can see some of them on my Portfolio page. The trick is to achieve the right balance and weight. Too heavy and it’s almost unusable. The balance is really the weight of the mallet head in relation to the length of the handle. It’s actually a bit hard to describe, but hold one in your hand and you can quickly sense one that’s out of balance (Ever hold a battery operated drill/driver without the battery? That’s out of balance).
I have purchased quite a bit of turning stock to make more. I have all sorts of wood species including Ebony, Lignum Vitae, Cocobolo, Tiger Wood, Holly, Bubinga, and a half dozen other species. The harder, denser pieces I’ll use for the mallet head. Lignum Vitae is the classic wood to use for mallets because of it’s density. There are many other woods that are nearly as hard but much better looking, like bubinga and cocobolo.
Turning Mallets is a great way to hone one’s skill at the lathe. Plus it’s a good excuse to buy usual wood species since you only need small quantities. The pictures I’ve posted are only samples I’ve turned (walnut and maple) recently.