Simplify the following text for a Grade 8 native English-speaking person.
Original: In late 1989 a team led by gemstone prospector Heitor Dimas Barbosa uncovered in a small mountain range what some consider to be the finest tourmaline crystals ever found .
Simplified: In late 1989 a team looking for gemstone and led by Heitor Dimas Barbosa found what some people believe are the best Tourmaline crystals ever found .