It seems to be a generic brand and the little mark on the clasp is likely the manufacturer of the clasp, not of the necklace.
Most pearl necklaces are generic.
Are you thinking you need to insure it, and looking for replacement value? If so and if the tag doesn't have a price on the reverse, perhaps you could just ask you mother what she paid for it. However I don't think it needs to be insured. It is not that high-end.
Regarding quality/value, circlé or circled pearls are the least costly types of Tahitians and SSP (because they are the most common.) Pearls with 1-2 circles are the most valuable of circled pearls, and the more circles there are the lower the value, because circles can interfere with the appearance of luster. Yours have more circles, therefore slightly lower market value.
But they are still cultured sea pearls! And many people like circles! I do. I own circled Tahitians, white SSP and GSS. I find the shapes interesting.
I see some of your pearls have tokki. Those are the little knobs on the ends of some of the pearls. There used to be a great article about tokki pearls in SSEF magazine (Swiss Gemmological Society) and I looked for it so I could give you the link but the article is not online anymore. These little knobs sometimes form as separate little pearls as a result of the culturing process, and then they attach themselves to the main pearl, and then the oyster lays down nacre over the entire thing. They are cute-- but take care as they could break off. Specifically be careful when you remove the tag as the white part of the tokki pearl near the tag could be fragile. Edit: See photo in my next post for pearls that you should handle with care when removing the tag.
I hope this helps. You have a nice wearable necklace there!
However, if you were asking about value because you don't care for the necklace and are wondering how much you could sell it for, this is our standard advice: check eBay for SOLD listings of a similar strand. That will give you an idea of what people seem to be willing to pay for that kind of thing at the present time.
