I would suggest starting with your tools. Really sharp tools,as well as technique will eliminate the need for most of the sanding.Not all of it,but a majority of it. Then,when you sand,go through the grits ,at least to 400 (I go from 400 to 1500 grit),while the lathe is running.Then,shut off the lathe,and sand with that same grit in the direction of the grain. That should eliminate the sanding 'rings' from sanding while the lathe is running.Then,turn the lathe back on,and using a piece of a brown grocery bad,go through your sanding motions,using plenty of pressure.This tends to burnish the wood,making it silky smooth,and you shouldnt have any marks remaining.If there are,go back and sand some more with the lathe off.Then try the brown paper bag again.Shellawax should give your rosewood a beautiful shine.Try wiping the shellawax on the piece with the lathe off,and let it set a few minutes before polishing it.I hope I helped you out.Good luck,and let us know how it turns out. Youre welcome to pop in the chatroom here on www.wooders.com/wooderschatroom.html and get to know a few pretty good turners. If your turning rosewood,you must already be addicted to turning.Its loads of fun!