These 24 mm x 50 mm slivers of glass are really meant for microscopy. After a sample is placed on glass slide, then these covers are used to protect the specimen - and - to protect the microscope lens. They arrive in a nice little protective box. Each slide measures just about 1 inch by 2 inches and is between 0.13 - 0.17 mm thick (size #1). Boxes are measured by weight and this one-ounce package contains between 75 and 100 pieces.
These are really too fragile for jewelry bases, but they're great for collage, assemblage and the like. You can double them up for extra strength, too!