[TPIN] Dating an antique cornet

[Achias1 at mchsi.com]

(Not THAT kind of dating)

i'm still working on finding any info on the DeJaques cornet that I have. It's obviously a stencil, and 
probably was made in Germany.

Is it possible to get a rough idea of how old it is by it's features?

One repairman told me that since it has three guides per valve, it's probably from the 19teens.

Another told me that since the bottom valve caps are nippled, it's probably pre 1890.

The case was covered in leather, but most of that is flaking off now. The cornet was held in place by a 
spring-loaded vice around the valves.

Stamped onto the A slide are the letters, "LO" meaning this instrument is in low pitch.

The unmarked mouthpiece has a funnel cup, but is not as deep a cup or wide a rim as my Wick 4W.

Is any of this identifying it's age?

Dave