Dry rose + saffron. Here's my earlier review of Opone:
Like most of the scents I know from Diptyque, Opone is based on a simple accord, in this case rose and saffron. These two notes are so tightly integrated that I can hardly tell where one ends and the other begins. This in itself is a remarkable feat of perfumery. The astringent quality of saffron keeps the rose from becoming too sweet or cloying, while the rose prevents the saffron from turning into rice pilaf.
Again like other Diptyque fragrances, it is resolutely linear, so that once you've smelled the top notes, you've experienced the whole thing. I suppose there's an advantage to this, in that you'll know immediately whether or not you like it, and there won't be any unpleasant surprises as the hours pass.
Opone is attractive and well-executed, but it ultimately fails to excite me as do some of the more aggressive rose fragrances, including Black Aoud, Royal Aoud and Sa Majeste la Rose.