Celebrities Tom Kaulitz (29) designed the ring with which he and his girlfriend Heidi Klum (45) in marriage early. That tells a friend of the couple to PEOPLE.

When Tom, the singer of the German rock band Tokio Hotel, once decided had to get Heidi to marry him questions, he pulled all the stops. He designed the perfect ring and also went in search of the perfect gemstones. A friend of the happy couple tells PEOPLE that Kaulitz is not easy from made. “He knew that Heidi’s favorite color was green, so he searched for the perfect green alexandrite, and to the right diamonds to him to accentuate.” The choice was not just about alexandrite. Not only is that a green gem, but he also changes color. In the sunlight he is green, but in the light of a lamp, the rock red eyes.