It was a common process in Asia and South America as late of the 1990's.Mostly do to the lack of modern faceting equipment....
The stone appears to be "native cut" it was cut to add weight to the stone without cutting the proper angles.
There is nothing in your photos that remotely resemble pyrite.....
It probably won't help much.
The apps are not reliable.
Take a look here...... https://www.antiquers.com/threads/posting-a-thread-and-uploading-pictures.15990/
Edit them to full image.
Where was it found?
Looks like pegmatite.
A good piece of sliced iron meteorite looks like this..... [ATTACH]
Maybe pyrite/galena with quartz.
Depends on what you call mass produced.It's made up with cast pieces for 5 stones each and soldered together.
acorns?
Is there a VL mark below the 925 on the other side of the pin stem?
Letter holder
Bought at a local jewelry/department store or mail ordered and the "P" was poorly engraved by bench jeweler at local shop.
Is the top surface dirty or is there a big air bubble there?
Natural and synthetic pink sapphires can glow.
It has a cut on both sides of the shank,usually called half shank replacement.
The base shape may have been,the silver balls and bezel were soldered on.
Separate names with a comma.
