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Our Core Values

The Royal Coster Passport explains our core values. These three values are:

  • Flexible
  • Family & Connection
  • Dedication & Service

The three values lead us to six Guiding Principles:

  • Craftsmanship
  • Openness
  • Supportive
  • Trustworthy
  • Exceptional
  • Royal

These guiding principles are the foundation of COSTER. Our mission is to go Beyond Expectations.

Discover our Diamond Rings

Whether you're looking for a diamond solitaire ring, an alliance or eternity ring or a diamond trilogy, we have it. And what we don't have, we can make.

View Collection

Book A Royal Experience

Learn more about our 180 years of diamond craftsmanship and our impressive history during an amazing guided tour.