Here are some of the leading national suppliers of metal refining in the United Kingdom:

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Leading National Suppliers of Metal Refining in the UK

1. UMICORE

   • Overview: A global materials technology and recycling group, focusing on precious metals refining.
   • Website: umicore.com

2. Johnson Matthey

   • Overview: A global leader in sustainable technologies, providing materials and services for refining and improving metal products.
   • Website: johnsonmatthey.com

3. BASF

   • Overview: The company offers precious metals refining services, including the recovery and recycling of precious metals.
   • Website: basf.com

4. Metalor Technologies

   • Overview: Specializes in precious metals refining and is involved in various sectors including jewelry, electronics, and health.
   • Website: metalor.com

5. Heraeus

   • Overview: A technology company that provides products and services including precious metals refining, serving various industries such as automotive and electronics.
   • Website: heraeus.com

6. Sims Metal

   • Overview: Engages mainly in metal recycling and refining, providing comprehensive recycling solutions.
   • Website: simsmm.com

7. Ward Recycling

   • Overview: A leading metal recycling company that offers services for refining various metals.
   • Website: ward.com

8. Intercontinental Gold & Metals Ltd.

   • Overview: Focuses on precious metals refining and offers a wide range of related services.
   • Website: igmeurope.com

9. C. T. Johnson

   • Overview: Specializes in precious metals refining and offers comprehensive recovery services in the UK.
   • Website: ctjohnson.co.uk

10. RMC Group

    • Overview: Involved in the recycling and refining of non-ferrous metals, including precious metals.
    • Website: rmc-group.com ```

This list includes a mix of companies that specialize in various aspects of metal refining, particularly precious metals. Let me know if you need further detailed information about any specific company or area!