We are the Jewelry Industry's Leading Jewelry Association. Explore the finest Jewelry, Diamond Manufacturers & Connect with our Members. ow Retailers Can Add Business Value Through Adopting a Sustainability Strategy, The Plumb Club connects its Members and their Customers and Helps Shape the Future of the Jewelry Industry, The Plumb Club is an Alliance of Supply-side Jewelry Industry Companies, The Plumb Club requires all Members to be RJC Certified, The Plumb Club is a Jewelry Association of Responsible Companies Recognized for Leadership,