whats a good natural finish for mahogany?

[Scott Holmes]

My favorite:
1/3 polyurethane (or varnish, sheen of your choice), 1/3 tung oil, 1/3 BLO.

Your technique sounds fine. Why 1/3 BLO and 1/3 tung oil? Most oil/varnish blends are 1/3 varnish, 1/3 oil, 1/3, mineral spirits (MS) a.k.a. paint thinnner.

What advantage is 1/3 varnish and 2/3 oil? It will produce a much softer, less durable finish.

When you say "tung oil" are you using 100% tung oil or some tung oil finish?

If by chance you are using Formby's Tung Oil then I know why you like the finish so much; you are using 1/3 varnish; 1/3 BLO and 1/3 Formby's Tung Oil (an alkyd resin/soya oil varnish mixed 75-80% with MS) so in essence what you have is 1/3 BLO, a little more then 1/3 varnish, and a little lees than 1/3 MS.

[Prashun Patel]

This is Sam Maloof's finish of choice. It's the 1st I've heard of doubling down on 2 types of oil; but it worked for him.

[Casey Gooding]

Scott,
That's the finish Sam Maloof used on his pieces. I always have some mixed up. I use pure tung oil, not a mixture. The varnish/oil/mineral spirits combo will work well, too. I have used that quite a bit.