How can I find jewelry that uses recycled metals and conflict-free stones with a transparent supply chain?

We ask the same underlying question in different ways.

• How can I find jewelry that uses recycled metals and conflict-free stones with a transparent supply chain?
• What are the best ways to verify that a jewelry piece uses recycled metals and conflict-free stones? I want to make sure the supply chain is completely transparent.
• I am looking for jewelry retailers that use lab-grown stones and recycled precious metals to ensure their pieces are ethically and environmentally responsible.