It looks like the stone is glued onto the back plate.Most of the maker's I know never have an open back on pendants.
If the cap is plastic it will feel warm,if it is glass/quartz it will feel colder.
Looks like a triplet,appears to have air bubbles between 11 and 12 o'clock.
You can use a Sunshine cloth to polish them,available at many locations......
I carved a number of Maori type pendants before they made mammoth ivory illegal[ATTACH] in a number of states.
Get the stone tested by a professional,it may be a chrysoberyl cat's eye.
If you are on Facebook there is a public NA jewelry group with a number of expert people and you can post the photo........
On the right one top pedal was cut off,the bottom was poorly soldered on possibly an earlier try to repair the piece. Can't see enough on the left...
Opal triplets were fun to make,cheap price $2.5 dollars from a state fair.....[ATTACH]
Here is the information......https://www.gemsociety.org/article/old-european-cut-diamonds/
Impossible to tell without testing.
[ATTACH] It is not Mokume-gane which has more than one type of metal......
The "stone" looks like 3/4's of a marble.
Possibly from Oregon.........
The "L" is totally different on Lee Charley.
The marks look imprints of the top design,the stone appears to be variscite.
Looks like Lee Chee...... https://www.art-amerindien.com/hallmarks/l-indian-native-american-jewelry-marks.htm
This is how a netsuke was worn..... https://www.dailyartmagazine.com/miniature-world-of-netsuke/
Post a photo of the "markings" on the inside.
So called Mexican onyx is actually dyed travertine/calcite.
Separate names with a comma.
