I love it! But it doesn't look like the style of Jennings Brothers....and from what I read they always worked in spelter....and that sure doesn't look like spelter in any way to me...looks more like pewter.
Maybe it's a little more arts and crafts than art nouveau?
Even has a little of the southwestern or Aztec look.
Does it hold a magnet...I know likely not but I had to ask!! LOL!

I thought arts and crafts too but the owner of the booth had it for sale as art nouveau. I also agree with you on the south western and aztec look too! It does hold a magnet, is that a bad thing..LOL? It reminds me of some tiffany pieces of I seen but I am dreaming that it is...LOL!!!!

A dealer from ebay just said it's probably 1960's but in my opinion, I don't think so...mmore like late 1800's or early 1900's.

It holds a magnet? All over? try lots of places...
That means it's steel....or possibly an alloy called white brass a nickle alloy.
Wow! Who worked in steel?

Holds the magnet all over, even the bottom too.

My guess is cast iron with worn brass overlay. Not uncommon in old letter holders.

And yes, I do think it's probably Jennings Brothers.