"Master working" a sword will give you +1 damage, but that is all. The sword is of exceptional quality though it is difficult to have one look 'exceptional' without making it magical. Maybe adding gems to the hilt, or the color of the blade is a little different. But all in all, there is no requirement for 'masterwork' in terms of how the sword looks. Also, this does not make the weapon magical. Of course, you could go for a "Masters Blade" but that is much more expensive and it will be magical, you will still get +1 damage, doesn't break cap, but if your character is a "weapons master" the blade will give him one additional master's strike. Again though, a "Masters Blade" is 24 craft points while making a weapon "master work" is only what, 4? 8? I don't remember off the top of my head. So to state again, there is no color/look requirement for a "Master work" weapon, and to clarify for Tony yes you can have just a master worked weapon without it being magical.