Possibly Russian necklace

1

I’m trying to identify the origin, maker and period of this necklace. It’s 21 inches in total and may possibly be Russian. It has what I think are makers marks of MS 1 or it may be from the Cyrillic alphabet.

IMG_8070
IMG_80701848×3998 2.11 MB

IMG_8071
IMG_80713024×4032 3.32 MB

IMG_8067
IMG_80673024×4032 3.55 MB

Any help appreciated