Queen Mab

Greetings all.
I hope you can all bear with me for a while. I'll probably be posting a bit more than I really ever have. I've recently acquired several watches and a really nice case and for the sake of marital bliss, I'm probably going to try and auction some of them off. Along those lines, I'm trying to figure out some of what I have. This first one is a cute little thing. I believe it's a Queen Mab from the New England Watch company. And that's about all I have found. I'll post a few pictures and hopefully see if you can shed a little light on things. This first picture shows size and face.

This is the watch completely open.

Here is the front and back. It really is a pretty case and very sharp.

Sorry the previous shot looks a little blurry. I think I goofed when I reduced the size of it. Here is the movement and markings.

And this last one is the only hallmark on the inside of the case. I have no idea what it means. I've seen a couple of pictures that gave a guaranteed year but this one doesn't have that. Any idea what kind of case this is? Gold? Gold filled?
Any and all comments or information is very much appreciated! Thanks everyone.

its in price guide is duplex escapement
size zero price from $35 to $85

E d,
I would take a guess that that TKGF likely stands for 10K Gold Filled, at best.
Bill

Thanks for the info gentlemen. Peter, thank you. I put my book somewhere so I wouldn't lose it, so obviously I can't find it right now. And Bill, I'm sure you're right. Never even occurred to me!