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
Mohs surgery The fault of the surgeon is failure to understand pathology laboratory methods, and failure to follow the standard of care for adequate surgical margin. Usually, the cure rate using standard bread loafing is very low for narrow surgical margin and a large tumor, and very high for large margins on small tumors. Some dermatologists, oncologists and health economists say that Mohs surgery is overused, because it is highly profitable. Dermatologists may perform the surgery on areas of the skin where it is not necessary, or perform unwanted cosmetic surgery. The incidence of Mohs surgery increased by more than 400% between