The state stipulates that precious metals must be marked with the material name and purity of precious metals, and must also have factory labels. Yours has no gold logo, at least it doesn't meet the national requirements.
See if there are any orders. You can go back to this jewelry store. If you are tough, you can go directly to the industrial and commercial bureau. The premise is that there must be a list, otherwise it is difficult to say where it was bought.