Triangle-C Trademark

figure 2

figure 3

figure 4

No trademark registration has been found for this trademark.

In looking for some evidence that was actually used on the glassware in the early to mid-20’s, there are several possibilities. The best evidence is a Primrose bowl with a stamped in the bottom, Research indicates that the Primrose color was introduced in early 1923 and does not appear to have been produced for more then a couple of years.

Before discussing how long was used, a distinction must be made. There are two marks of differing sizes. Both are triangles of three equal sides. One measures approximately 8mm per side (figure 1) while the other is 5mm (figure 2).

The 8mm size is the older mark and is the one on the Primrose bowl mentioned above. It has also been observed on Rubina Honeycomb pieces. Findings show that Rubina was introduced in 1925. Although we have no specific evidence of usage of the large mark in 1926, one would think that is was and that the switch to the smaller mark occurred simultaneously with the introduction of the CAMBRIDGE paper label in 1927.

The thought occurred that if the small started at the same time as the paper label, maybe both were discontinued at the same time. This does appear to be substantially the case. Many new lines were introduced by Cambridge from 1927 thru 1937 including Decagon, 3400, Tally Ho, Seashell and, in 1936, Caprice. We have observed the on all of these lines but in decreasing frequency on later lines. For all practical purposes, the usage of the small does coincide with the paper labels with the same date range of 1927-1937.

In summary, we have the large (8mm) used 1923-1926 and the small (5mm) C used 1927-1937.

The figures above show examples of how the mark was presented in the trade advertising. Figure 3 comes from a December, 1927, advertisement and figure 4 comes from an August, 1930, ad.