Both oils may benefit the horn. Just do not over do the treatment. You don't want it to soften very much.
This is the very first that I have heard that one may wish to "treat" horn. I have only kept it clean.
Remember that this is, even organic, a dead material. Feeding the fibres is BS.
Best,
John


Humble member of the League of Extraodinary Gentlemen (LEG). Joined 14 March, 2006. Member #1.