Mineral necessarily constant for all sides, which is a function of its structure; crystallographic weakness renders some directions softer than others. An example of this property exists in kyanite, which has a Mohs hardness of 5½ parallel to [001] but 7 parallel to [100]. The most common scale of measurement is the ordinal Mohs hardness scale. Defined by ten indicators, a mineral with a higher index scratches those below it. The scale ranges from talc, a phyllosilicate, to diamond, a carbon polymorph that is the hardest natural material. The scale is provided below: Lustre indicates how light reflects from the mineral's
Softer, Softest Hole's performance on "MTV Unplugged" on Valentine's Day 1995, Love introduced the song as "[being] about the girl that always smelled like pee in your class" and also claimed it was autobiographical and not about former MTV producer, Tabatha Soren. Despite being credited on record as a collective authorship by all members of Hole, according to Broadcast Music Incorporated's website, the authors of the song are only Eric Erlandson and Courtney Love. A promotional music video was never recorded for "Softer, Softest", however, the version of the song performed at "MTV Unplugged" in 1995 was used a music video though