When you are looking for eco-friendly metal packaging suppliers, there are several key considerations to keep in mind, as well as a variety of companies that are leading the way in sustainable practices. Here's an overview based on the information provided:

1. Sustainability Commitment: Look for suppliers like Amcor, which has pledged to make all its packaging recyclable or reusable by 2025 and is a core partner for the New Plastics Economy initiative of the Ellen MacArthur Foundation. They are focusing on materials like pure polyolefins (PE and PP) and limiting the use of materials like nylon to 5% of the overall composition to meet high sustainability standards.

2. Recyclability and Reusability: Choose suppliers that prioritize creating packaging that is not only recyclable but also reusable. This reduces waste and aligns with the growing demand for eco-friendly packaging solutions.

3. Lifecycle Assessment: Opt for suppliers that conduct a full life cycle assessment (LCA) of their products, considering energy and material inputs, waste, water consumption, and carbon footprint. Companies like Amcor use their own assessment systems, like the 'ASSET' system, to measure environmental impact.

4. Certifications and Partnerships: Consider suppliers with certifications from recognized organizations and those that have strategic partnerships aimed at enhancing sustainability. For instance, Amcor has signed agreements with chemical companies like SABIC to convert plastic waste into monomers, reducing the use of petroleum-based raw materials and emissions.

5. Innovation in Materials: Select suppliers that are investing in research and development to enhance the composition of post-consumer recycled (PCR) plastics and are open to innovative packaging methods.

6. Industry Recognition: Suppliers that are recognized by industry experts and have received awards for their sustainable practices, like Elopak earning the World Packaging Organisation’s WorldStar 2022 Packaging Award, are a good choice.

7. Circular Economy Practices: Work with suppliers that follow circular economy principles, aiming for zero waste and promoting the use of recycled content in their packaging.

8. Transparent Sourcing: Choose suppliers that are transparent about their sourcing practices, ensuring that the materials used are ethically and responsibly sourced.

9. Customization and Innovation: Suppliers that offer customization options and are open to adopting future innovations in eco-friendly packaging, like Juyou Tin Box Manufacturer, can help your brand stand out while remaining sustainable.

10. Market Leaders: Consider working with market leaders who are known for their sustainability efforts and have a track record of providing eco-friendly solutions, such as those mentioned in the Top 10 Sustainable Packaging Manufacturers list by Packoi Team.

By considering these factors and researching suppliers that meet these criteria, you can make an informed decision when choosing an eco-friendly metal packaging supplier for your business. Remember to also look at the specific needs of your product and the sustainability goals of your company when making your selection.