25 augustus 2011 heeft de burgemeester van Amsterdam, Eberhard van der Laan, een bezoek gebracht aan de fabriek van Coster Diamonds aan het Museumplein. De burgemeester werd rondgeleid door de panden en was zeer onder de indruk van hetgeen het bedrijf al vanaf 1840 weet neer te zetten.

During the hospitality Welcome Gala at the Beurs van Berlage, Pamela de Jong, senior sales manager of Coster Diamonds, Amsterdam, received the Welcome Award 2008 in the retail category.

The 4th winner of the diamond is Ms. C.P.A. Elfers - v.d. Veen. She won a beautiful diamond worth € 300,-. In cooperation with the restaurants Paardenburg, Sophia and Keyzer, Coster Diamonds has an offer where the consumer receives a gift. With this gift they visit Coster Diamonds where the authenticity of the diamond is checked. Offer valid until the end of February 2010.

Today, an agreement has been signed in the presents of Notary Frank Sterel of notary office Sterel Amsterdam. In the agreement it states that a portion of the shares of Coster Diamonds will be devided to Mr. C.J. Noomen (President) and Financial director Mr. E. Hotie. As of today, these two directors will be the co-owners of the since 1840 established Coster Diamonds.