Tom Thumb sets were made by the Homer Laughlin China Company in the early 1930s. The set was made up of three pieces; a Wells 7" plate, Purina bowl, and an Ovaltine shape mug. Each piece was glazed in vellum (a glaze originally developed for the Century shape) with the rims trimmed in green. There were at least eight different decals featuring Tom Thumb with one of the following: frog, butterfly, beetle, mosquito, turtle, fish, blue bird, and mushroom. The first time the set appeared in a collector's reference book was on pages 138-139 in The Collectors Encyclopedia of Fiesta, Fourth Edition, by Sharon and Bob Huxford.
The official treatment number for the line was W-9633. This number was usually stamped on the bottoms of the mugs. Bowls may or may not be marked, and plates were given either a special HLC-Vellum mark or the general backstamp with date code.
Tom Thumb sets were sold in various department stores across the country. The Miller & Paine Store in Lincoln, Nebraska sold the three-piece set for fifty cents in December of 1933. Kaufmann's in Pittsburgh sold sets at forty-five cents in March 1933, as shown below.