Desert Iron wood has the highest specific gravity of any wood that I use whether it be for plane making or otherwise. In the wood data base it is listed as 1.21 specific gravity. If you compare it to Macassar Ebony at 1.01 specific gravity you would think it would be even harder.
The working characteristics are considerably different and in my experience the Macassar Ebony actually seems harder. I first imagined that Desert Iron wood might be particularly hard on the edges of chisels but actually this material gets out of the way of a chisel pretty well, however when trying to chisel in a tight inside corner it has a bad habit of fracturing.
By and large the working characteristics of this material are much different that I had originally thought. The initial whittling with a chisel to excavate material prior to the beginning of the rasping process goes quite well, easier than I had imagined. Rasping can tend to tear the grain and a coarse rasp needs to be followed by a finer tool.
This material is very abrasion resistant. Sanding this material can take up to 3 times longer than any other material I use in plane making.
The grain structure is very unusual which probably explains the tendency to fracture and is just a bit coarser than most dense woods.
Polishing this wood was certainly a learning experience. When applying a shellac polish you certainly will need to apply a couple coats of finish dedicated to filling the pores, otherwise the unique texture of the grain will show prominently.
As much trouble as this wood is to work and finish properly you are rewarded for your efforts in the end. Nothing looks quite like this material. When polished to a high level some pieces remind me of looking into a sunset. Within the same piece it's quite varied and interesting. You see something different everywhere you look.
In other words it's quite a worthwhile pursuit,
"The difference between a smart person and a wise person is that a smart person knows what to say and a wise person knows whether or not to say it."