What is this thing?

That's freaking great! Awesome pics.

So, while I can't see anything to give you more info about the knife itself, at least not any more than others have already covered, you are in position to be able to have a really cool little knife.

There's no visible red, orange, or yellow rust. That's great. The interior looks clean enough that you've got plenty of time to get a better product to clean it the rest of the way. Typically, the gun oil and a few qtips will get that level of gunk taken care of in a half hour or so, maybe less.

That means all you have to do is basic maintenance from here. Keep it oiled, and I do recommend the same things again. The blades are carbon steel, so a bit of an oil coating on them is good.

The scales are showing their age, and there's only so much you can do with them. I'm 99% sure they're celluloid (though my eyes aren't what they used the be). That stuff is really pretty, but degrades over time, and there aren't really any methods to prevent that. The best you can do is keep it clean and dry, away from sunlight when not in use. Some folks will apply other materials to keep scales like that in place, but it's never perfect. I have done some of that in the past, mostly with clear epoxy and careful polishing, but I regard it as a last ditch effort, but once celluloid gets degraded enough, there's really nothing else to do.

That being said, there's likely a decade or two of life in those scales, barring accidents.

Sharpening is fairly easy on those older knives, but if you need info, just holla.

Nice little knife there, it's cool to see someone taking the time to put it to use :)

So building on this I did some light perusing on the internet and got a little hyperfixated, but found some tiny things.

This was the closest Solingen I could find, but the caps on the end don't match and I doubt the little rivets would be completely hidden by the patina, so that's probably not it.

Then on Etsy I found this posting That has one that looks identical but with no further information on it and listed as "Richards" (Richards, Sheffeild). And This one that just doesn't have the smaller blade but is listed as Solingen.

I went to try and double check that patent number and I'm not finding what they did, but I also don't know what I'm doing. The German patent office has 2 companies with that patent number, one for Naproxen and one for the moving blades on hair trimmers.

But then I found This guy with the exact same patent number on it but marked as Hammer brand. It's very similar but has 3 blades instead of 2.

This leads me to believe that the patent is not for the whole knife but the blade specifically that was made by Solingen and sold to other knife manufacturers who affixed them to their own pocket-knife-pieces. With all this in mind, I'm starting to think it's likely from Richards, so I refined my search again and found this guy as the best bet: knife. But instead of the patent number on the tang they have their own stamp. So my best guess, after a tiny bit of research, is that Richards probably made it, but it's not their top of the line stuff with their branding but something akin to a "store brand" where they used their typical parts but used the blades from Solingen. I'm still assuming it's Richards because they were the only brand I could find that made knives with all the parts (Same end caps, 2 blades, pearl handle with no rivets showing, shape) together. Other brands seemed to have some, but not all parts combined. But with the tang stamp being off, I can only assume it wasn't an "official" Richards brand but put together by them and sold by another party as a cheaper alternative.

If you're still curious, that All About Pocket Knives site seems to have active forums with knowledgeable people who could probably (almost definitely) find or know more than me. I don't know anything about any of this and was just a bit bored this morning while drinking my coffee, so I definitely suggest asking them for legit advice.