Dial Back Case Mark Movement Closeup

The Waltham Jewel Series watches consisted of grades Diamond, Ruby and Sapphire. Some of the movements are marked Maximus instead of Diamond and there appears to be no difference between them. Both the Maximus and Diamond Grades are 17 jewel. This is one of two examples I have seen that is marked both Diamond and Maximus. 

The Waltham serial number records have two runs of the diamond grade jewel series listed as "Opera" model. The run at 18,059,001-200 is listed as Diamond Maximus. This watch is from the other run that is listed only as Diamond. It seems likely that all 400 of these watches are marked Diamond Maximus. This is the last run of Diamond grade from 18,134,501-700.

The case is the Waltham "Opera" case that has a large dial and a lovely filigree plate surrounding the movement to increase the size of case the movement fits. Waltham apparently only housed adjusted watches in this way since the filigree is marked "Adjusted." 

The watch is cased in an interesting way sandwiched between the filigree plate and the dial. The dial is screwed on from the back and the screws fasten the dial to the filigree, not to the movement. The movement is then attached to the filigree also with normal case screws. To disassemble the watch, you need to remove the hands, then take the dial off from the filigree and finally remove the movement from the filigree. If you try to loosen the case screws and take the watch out from the front as a normal watch, you will damage the dial. If you take out both the dial screws and the case screws, only hands are holding the dial to the movement.

It is rare to find one of these watches with a really sharp dial and the dial on this example has some small problems. However, it is a very unusual and interesting example of the top of the line in the Jewel Series. It is interesting to note that the success of the Jewel Series led Waltham to produce an Emerald Grade 21 jewel watch. However, by the time the Emerald was being produced the quality specifications had slipped considerably. Most of the Emeralds are found cased as wristwatches.