Best way to get your Martini identified is to post pictures. Martini's should have a serial number on the receiver face or bottom edge of the receiver frame. Serial number are sometimes also found on the major pars.
The Martini Henry pattern barrel tenon should be 1"-14 TPI. Greener is 1.075"-14
Mk Ito Mk III Pattern
MK IV MH Pattern
Greener Pattern
Commercial action
Francotte Pattern, large and small
The Military Martini's are well marked and should be fairly easy to identify. There were commercial versions of the military guns called Volunteer patterns. They were not always marked or may have what appear to be proof marks that are actually makers stamps.
Greener made the Egyptian Guard guns and they are often seen on the market as actions.
Commercial makers also made patterns very similar to the Greener Pattern
The Francotte guns are most familiar int he small martini action that we know as the cadet. There are a lot more different models Francotte Martinis than the cadet, the cadet a BSA 4B is the most familiar in the U.S. The Francotte was also made in a large action
Most Martini's are English and Belgium made. But they were also made Germany, U.S. and Sweden.
There is also the Khyber Pass models. They are made, rather crudley at times in the Afghanistan Pakistan border region. The metallurgy is questionable but the design of the Martin is sufficiently strong that you are not likely to get hurt if one blows.
So post us some pictures of your action and any marks it might have and we will see if we can figure out what you have.