I have turned many exotic tropical hardwoods in my life. I did even travel the art show circuit with my bowls, etc , only to switch to smaller turnings: pens. I made and sold thousands of them... lost thousands of $ each year. Thank goodness for my Teacher's Retirement income... it kept the lights on. I still have lots of wood... maybe it is time to make some grips!
Nearly half of the almost 5,000 acknowledged species of trees in the world are found in Brazil. Pao ferro is the portuguese term for 'iron wood', a generic wood encompassing many species. They are generally very dense... in fact, one type finds a lot of use in pier pilings! I bought some Brazilian modern suede leather furniture where the frames were made of pao ferro nearly three decades ago... those frames were stout - and heavy. The wood was very dark, and nearly figureless... not a pretty choice for a set of grips. There is an American version - ' desert ironwood'.
Probably the prettiest wood I ever worked with was cocobolo, from Honduras. It is nicely figured and ranges from yellowish orange - red - deep brown - near black, all in the same boards, at times. Like other rosewoods', it is easily finished by a penetrating oil and/or a wax finish. Sadly, it's dust is an allergen - and it can send some into shock. Wear respiratory filters when sanding or cutting it. The worst smelling wood must be the W. Equatorial African Zebrano or zebrawood - I maintain it smells like the zebra cage at the zoo.... others insist it is named for it's light/dark bands. Actually, a prettier, and more dense and waxy/resinous version, is Mexican bocote... I may just have to try it for some grips... and, it doesn't stink as badly!
Stainz
PS I have had a resurgence of my childhood asthma over the last few years... the woodworking went bye-bye... but, I picked up guns and shooting!