After staring at it all I can see is essentially https://www.amazon.com/DharmaObjects-Tibetan-Buddhist-Mantra-Sterling/dp/B01BPH9QEC in a slightly different font. You can look and see if you agree, So yeah: https://en.wikipedia.org/wiki/Om_mani_padme_hum .
I don't speak any language that uses similar characters and have very little knowledge of Buddhism but it seems that this is a very common sentence on jewelry so this is what I'm betting on.