Been there, tried different automatic tools for a client but ended up doing this by hand in Photoshop. Its painful but you get the best results - https://cdn.shopify.com/s/files/1/0181/8449/products/Mariage-Cercei-Swarovski_1_1024x1024.jpg?v=1351...
It's best to try and shoot on a white backdrop if you can. If you're on a Mac there is
I haven't used that myself. I normally use Photoshop. But that can be a bit expensive.