Vitreous detachment is the separation of the eye's internal clear gel (vitreous) from the eye wall or retinal. A ...
Artistic Wire craft wire is considered dead soft on the wire hardness scale, because it is bendy and pliable. This is a round (or twisted!) copper wire that has been colored with an enamel coating. This process has been developed to resist tarnishing, chipping, or peeling.
On the Mohs scale, a streak plate (unglazed porcelain) has a hardness of 7.0. Using these ordinary materials of known hardness can be a simple way to approximate the position of a mineral on the scale.