Compare and contrast the physical properties of streak and color in this 8 specimen mineral collection. Numbered specimens are approximately 1 x 1.5". Streak plate and key sheet included. Grades 5-12. Ages 10-18. Ages 10-18. Compare and contrast the physical properties of streak and color in this 8 specimen mineral collection. Numbered specimens are approximately 1 x 1.5". Streak plate and key sheet included. Grades 5-12. Ages 10-18. Ages 10-18.