Streak Plates - Black, 10 pk
American Educational Glass Streak Plates Kit, 1/4" Thickness (Pack of 10)
American Educational Hardness Collection with Test Kit
United Scientific GLP1X2-P Glass Streak Plate, 2" Height X 1" Width X 1/4" Thick (Pack of 10)
Mohs' Hardness Test Kit for Industrial Applications
Scott resources Rock Mineral Test Kit
Toysmith Mineral Science Kit
American Educational Classroom Collection of Rocks and Minerals
Toysmith Rock Science Kit
Deluxe Hardness Pick Set and Mineral Identification Kit, in Wooden Case