I've seen a few "Jeweltone" pencils over the years, always in blue, but until recently I never quite ponied up enough to bring one home. That changed a little while ago, when this one was a sleeper in an online auction:
The quality on these isn't the best. The plating is very thin, and they are your typical middle joint, nose drive pencil, although the plastic is really outstanding:
In fact, if the plastic looks familiar, it should. Here's the Jeweltone, flanked by a pair of later Diamond Points from the late 1930s:
Why it was branded differently is a question I wish I knew the answer to. One possibility is that Diamond Point created either a subbrand or a separately branded model. Another possibility, since these Diamond Points are from near the end of the line, is that a different company altogether assembled Jeweltones from parts bought from Diamond Point after the company closed.
More information welcome!