You can check the serial number of Van Cleef & Arpels jewelry in the following ways:

1. On Van Cleef & Arpels' official website, we can find the corresponding number by inquiring the model or name of the product.

2. Look for the number printed on Van Cleef & Arpels jewelry and see if there is a 750 mark next to the number.

3. Issue the Van Cleef & Arpels Jewelry Appraisal Certificate with Van Cleef & Arpels Jewelry Number.

I hope the above methods can help you find the serial number of Van Cleef & Arpels.