Building an exterior table out of Iroko for a client and they are hoping to subdue the yellow/orange hues that are present in some of the boards without going profoundly darker. I have read about tinting with a blue colorant to mitigate the orange in wood. Any other solutions that I am not aware of? I am also trying to bleach some samples (lye/H. peroxide) but not sure that will work out. Ideally the finish is going to be a penetrating oil (Teak oil or possibly Australian Timber oil) but will consider a film finish if it is necessary. The table will be under a covered porch so won't be getting a ton of direct UV light. Thanks.

No miracle product I am aware of that you didn't cover. I use green to kill the red hues. I've found blue to be the worst color for holding the color over time. Your customers have to make the decision on the finish. What level of maintenance they want to do will be the decider. Nothing lasts forever outside and they have to know that.

Hey Dave, I have a motto I live by, it is " never look for problems that can be avoided to begin with.!"
Was Iroko something you came up with to present to your client, or was that their suggestion or desire.? If yours, was it because you were looking for a cheaper alternative to a wood like Teak that had similar properties but was lighter in color, and could withstand the outdoor exposure fairly well.??
I ask because if this was your proposal, then you created an unnecessary problem that your now having to spend extra time and effort to fix.
Though I would normally suggest other ways to fix the color problem I won't, because, just like the other suggestions, though very worthy of consideration, none are permanent. Iroko on it's own will naturally darken with age, much like mahogany or cherry etc., so no matter what coloring you try, this will not stop the natural aging,
from changing what you do.! The one exception would be bleaching, although having not bleached Iroko myself, how much or how well it bleached is unknown to me. However I have bleached Teak with varying sucess.! But bleaching not only hides the natural coloration by taking it out of our perception of bandwidth of color perception,
So that to our eyes it no longer appears as a any color we can visually recognize, but also destroys any features that the wood itself has as to figure etc. It can give you a blank canvas to apply a new desired color, but it's no longer the same look as it has naturally, all the character is gone, you may as well paint it and grain it etc., as to bring back any natural look it had before hand. That said, best of luck on the outcome, and I hope your customer is satisfied. Hopefully, next time, you will think the whole job through much more thoroughly, before committing to a particular wood or finishing thereof, than this time.
Sincerely,
Chemmy.

I haven't worked with iroko but I have worked with lots of plantation teak which can get very orangy. Left out on its own the sun will kill the orange as I'm sure the sun will do to your iroko table. Also any penetrating oil will adjust the color. I would get your oil/sealer of choice and do some samples. That may solve most of your issues. Plus there are many tinted exterior oil/solvent sealers. You could also add automotive pigments to a solvent base oil. I've used pethalo green auto pigment in TWP products to kill red/adjust color on several front door/garage door projects.

Also, there's a product called rubio monocoat (that I've never used) that I've seen in online woodworking videos. It looks interesting for exterior projects.

my2cts

Thanks for the responses. Rich, I am not sure what they expect in terms of maintenance, but they will be informed that annually they will have to apply some type of treatment. This is through an interior designer but I am also dealing directly with the clients. Chemmy, I would say that you hit the nail on the head on just about everything, other than the fact that I got a sample of Iroko to show them, and it was much darker, (had been exposed longer to air/sun) and when I milled the actual lumber, it was much yellower. Some samples that I have left outside have already turned that much darker umber so the yellow went away relatively quickly. That said, the designer seems to now have decided that they want the new table delivered with the silvery grey patina that exotics get after sitting in the sun for a year. (Sigh) I have actually discovered a couple of products that are a mix of stain/oxidizer that create that look until the table can achieve its own patina. It is going to be on a covered porch that faces north and so won't get too much direct sunlight. Working on some samples now and it does turn the wood a muted gray which I am hoping will be acceptable to the client. Otherwise they will get it a year from now. Thanks for the responses.