... shape with full surface, good diaphaneity and low impurity, high strength, suitable for circular saws, frame-saw ... geological broaches. YWD 2140 comparatively regular crystal shape, high mechanic strength, beolonging to middle grade, containing ... low load. YWD 2120 irregular crystal shape , low strength, belonging to low grade, suitalble for grinding tools and wheels that work with low load. Large size ...