Study GuideGeology–The Earth's Components1. Mineral ProperƟesAt first glance, many minerals can look very similar. Because of this, geologists do not rely onappearance alone. Instead, they identify minerals using a set ofspecific propertiesthat are easy totest in the field or in a laboratory. Each property gives an important clue about what the mineral is.1.1 HardnessHardnessdescribes how easily a mineral can be scratched. Geologists measure hardness using theMohs hardness scale, which ranks minerals from1 (softest)to10 (hardest).•Talcis the softest mineral (hardness of 1).•Diamondis the hardest mineral (hardness of 10).In practice, geologists use simple tools to test hardness:•Aknife bladehas a hardness of about5.○If a mineral scratches the knife, it is harder than 5.○If the knifescratches the mineral, its hardness is less than 5.•Athumbnailhas a hardness of about2.5.Because the scale can be hard to memorize, many geologists use amnemonicto remember theorder of minerals on the Mohs scale.Preview Mode
This document has 10 pages. Sign in to access the full document!