Apart from not being purple, it looks like purpleheart, in terms of end grain, long grain figure.
If you can't easily dent it with a fingernail, it might be usable. Goncalo Alves is one of those woods where there can be a great deal of difference depending on the actual tree it is cut from. Some is stripey, some isn't.
I would probably go with a flat cross section on the belly, as it will have less likelihood to chrysal.