Ivory, DD, but it's not to my taste either. Give me buffalo horn anyday!

BTW Graham Greener had some harsh words to say about those guns apparently, doesn't believe they should be sold as Greener guns when Greener had nothing to do with them, other than make the original shotgun actions many decades ago. Perhaps he's just being conservative, but was strongly against the whole practice of making Greener shotguns into rifles. It might be a different story if that pair were reproved in the UK, but I strongly suspect they weren't going by who commissioned them!