For me I think you guys are messing up the whole look when you use a contrasting wood for the bone, butterfly. They shout, hey look at me! Seems the whole reason for the look is to show off all the wood. Not what holds it together. Besides, it's like any joint. It will be seen.
Friends don't let friends use stamped metal tools sold at clothing stores.
I used Maple (and the direction of the grain) in this case for the strength... Color was a side note - Strength was most important. :yes:
Same with the spline used... Maple is a hell of alot harder to rip apart than Walnut is when all else is equal (talking about the spline here and grain direction). A Walnut spline would have 'blended' better but would not have been as strong.
Good post. :thumbsup: