OP wrote a 2nd post: "Seem to be diamonds on clasp 800 stamped in clasp. Interested in finding the actual company that made the necklace?"
I see some things that make me think it may be an imitation strand (and the "diamonds" actually rhinestones.)
Pearls collect a patina of grime over time as a result of contact with skin oils, cosmetic/ lotions, and general pollution in the air.
Do this: First, clean the pearls by dampening a soft microfiber cloth and gently removing built-up grime. You could add a mild soap to the water you dampen the cloth with, if the grime is hard to get off with just water.
Then rub 2 of them gently together. what do you feel? Real pearl feel gritty. Imitation pearls glide more smoothly (if clean; dirty pearls can feel sticky and not glide easily).
Real pearls are cooler than imitation pearls. So another easy test is to place them in the same temperature environment with any pearls you have that you know to be either fake or real. Leave them there for half an hour or so. Then touch both of them to your lip (which is very sensitive to temperature). Compare.
You can also take the pearls to a local jeweler to test if the stones are actually diamonds.
There is an alloy of silver that is stamped 800. It's called continental silver and is 80% silver.