As of my last knowledge update in October 2023, here are some companies that are known suppliers of rubidium metal and related products. However, please verify their current status and product offerings as the market may have changed:

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Leading Suppliers of Rubidium Metal in the UK

1. Alfa Aesar

   • Website: alfaaesar.com
   • Description: A leading supplier of research chemicals, metals, and other products.

2. American Elements

   • Website: americanelements.com
   • Description: Specializes in providing high-quality specialty chemicals and materials.

3. Elemental Scientific

   • Website: elements-scientific.com
   • Description: Supplier of various rare and specialty metals, including rubidium.

4. Sigma-Aldrich (part of Merck Group)

   • Website: sigmaaldrich.com
   • Description: Offers chemicals and materials for research and development.

5. The Metal Company

   • Website: themetalcompany.com
   • Description: Supplier specializing in various metals and alloys, including rare metals.

6. Chempur

   • Website: chempur.com
   • Description: Offers a wide range of metal products, including rubidium.

7. Fischer Scientific

   • Website: fishersci.com
   • Description: A provider of laboratory chemicals, materials, and equipment.

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Please ensure to check the suppliers for their specific product offerings, availability, and regulatory compliance regarding the sale of rubidium metal, as this can change over time.