The most common facings for lapels and other trim on a dinner suit is satin silk, but an elegant alternative to satin is grosgrain silk. James Bond has worn dinner suits grosgrain in four films, from Tomorrow Never Dies to Casino Royale, and maybe in others. Grosgrain is a plain weave with crosswise ribs that are created due to a heavier weft than warp. Its most common form is in ribbon, and it can be found around the base of the crown on many hat styles. When a dinner suit is trimmed with grosgrain silk you’ll find the grosgrain trimming on a the lapels and on the stripe down the trouser leg, and on also covered buttons if the dinner suit has them. Pocket jettings shouldn’t be trimmed in silk. Whilst satin silk has a very glossy appearance, grosgrain silk has a rather matte finish but still contrasts nicely with cloths ranging from a classic wool barathea to a warm-weather mohair blend. I’ve been told it’s difficult to find grosgrain in wider widths, thus a ribbed cummerbund is typically made of a similar weave called faille, which has slightly heavier ribs. Faille is a decent match for grosgrain, though the finer grosgrain is better for lapels. The bow tie in the photo above is faille, whilst the lapels are grosgrain. If you’re having a dinner suit with grosgrain facings made for you, the same grosgrain silk can be used to make a perfectly-matched bow tie to go with it.
The image below from Die Another Day shows Pierce Brosnan wearing a midnight blue dinner suit with black grosgrain facings. Midnight blue and black facings are both acceptable for a midnight blue dinner suit, but a midnight blue bow tie to match might just be impossible to find ready-to-wear.