Riviera was a special line which used Century shapes in solid colors. Samples were made in December of 1937 with two colors from Fiesta: red and the original green, and two colors from Harlequin: blue (mauve type) and yellow. Ivory was picked up after 1943 when red was no longer used by HLC. Riviera was not exclusive to any one retailer and was carried by The Murphy Co., J.J. Newberry, Sears, and appeared in various wholesale and premium catalogs throughout the years. Butter Brothers sold Riviera as "Bohemia" in their wholesale catalogs.
Since Century lacked salt and pepper shakers, they were picked up from Tango to be used with Riviera. Tango had blue, red and Harlequin yellow so shakers found in those colors could belong to either line. However, maroon and spruce green were never used with Riviera and hence shakers in those colors belong to Tango only. Light green and ivory shakers come from Riviera.
Since the Century shapes and the solid color glazes were already in production, there wasn't much for the Art Department to develop. On December 15, 1938, Frederick Rhead notes the sauceboat and oatmeal were added to Riviera. There were also new items created for Riviera that had not existed in the older Century line.
The first newly modeled piece was the handled tumbler. On January 1939, Rhead notes the specifications for this piece: Take Harlequin tumbler, lines taken off, add handle to match Riviera. On February 2nd, trials of the handled tumbler were made both with and without the Harlequin rings. By the end of March, the Riviera handled tumbler (or as Rhead called it, "Newberry Handed Tankard") was released into production.
On July 10, 1939, Rhead mentions a "Juice set premium." The pieces were to be the same as Fiesta's with the following specifications: Tumbler same capacity, changes lines. Jug same capacity, mouth type." This set is commonly found with Harlequin yellow pitchers and tumblers in various combinations of the four standard glazes. In May 31, 1940, another Riviera juice set is ordered. Rhead notes the colors are to be jug in Riviera blue. Tumblers in Rivera blue, yellow, red, Fiesta turquoise, ivory and Riviera green. This set was intended to be a Murphy Co. exclusive, however, Riviera juice sets in the same colors were sent to Newberry's in August the same year.
On July 19th, more items were added to Riviera. Rhead lists these at "42s Riviera covered jug in red; 24s jug covered in green." Rhead commonly used trade sizes when listing entries for the pitchers. Here the 42s jug refers to the syrup and the 24s jug is the batter jug. The open batter jug was a standard item, but the cover (only in light green) didn't come about until July 1939. Furthermore, the Century syrup wasn't a standard Riviera piece. The entry explains why batter jug lids are found in light green (save some rare exceptions in red) and why syrups are in red. Though the retailer isn't mentioned, the pieces were made as a special batter set promotion.
On December 27, 1939, the next new shape for Riviera was ordered. Rhead notes "...to model Riviera Butter Dish after glass sample." Soon after it was released into production.
The last shapes modeled for Riviera didn't go into production: the compartment plate and a console set made up of a long bowl and candle holders. A memo dated July 17, 1940 discusses the compartment plate:
We have discussed with Mr. J. M. Wells the possibility of making a Riviera compartment plate. Mr. Feuchtwanter [of the Chicago office] has a customer who can use a large quantity of these if we can supply them with the right item.
The first Rivera compartment plates came out of the kilns on September 9, but had to be remodeled. Rhead never mentions the compartment plate again. There is one known to exist and it's pictured in Sharon and Bob Huxford's book, The Collectors Encyclopedia of Fiesta.
Would suggest you have modeled a Riviera compartment plate that would have approximately the same size and outside design of the Riviera plate. Then cut down the rim of the plate considerably and make 3 compartments. The partitions between the compartments should be fairly low so there would be no trouble about jiggering the item.
Rivera was produced until circa 1950.a Riviera was never meant to be marked, but some pieces are found with an HLC USA stamp. It's believe such pieces were marked for export. Regarding ivory Riviera and markings, if you find a piece of ivory (vellum) that is marked, then it's an undecorated piece of Century. Unmarked ivory pieces are almost always Riviera. This technicality is often overlooked by Riviera collectors who are willing to ad any ivory pieces to their collection whether they are Riviera or Century.
See also section on Century.