Quartz has the hardness of of 7 on the Mohs relative hardness scale.
The Mohs hardness scale measures the relative hardness of materials. It's a numerical value placed on the inherent ability to scratch or to resist being scratched. The greater a material's scratching ability, the greater its hardness. Frederich Mohs, a German mineralogist, used 10 minerals for standard measuring points to create a relative hardness scale. Listed from softest to hardest, the mineral standards are talc, gypsum, calcite, fluorite, apatite, orthoclase, quartz, topaz, corundum and diamond.
Instructions
Learn the Mohs Scale
1. The best way to remember anything is by throughly understanding it. Consider that "hardness" is ultimately caused by a mineral's atomic structure, internal arrangement and type of bonding. Talc, the softest mineral on the scale, has weak bonding, whereas diamonds have strong bonds and a unique hexagonal crystal lattice of carbon atoms -- forming the hardest substance on earth.
2. According to Tulane University, you can make your own hardness-test kit using a fingernail (hardness of 2.5), a silver coin (2.5 to 3), a copper penny (3), a knife blade (5.5), a piece of glass (6 to 7) and a steel file (7) to practice determining hardness at home. Start by scratching an unknown sample with your fingernail. If it was successfully scratched (a visible indentation was created), the hardness is equal to, or less than, 2.5. If the sample was not scratched, move on to the next harder object in the kit, the silver coin, and continue with the same procedure. If the coin scratches the sample, the hardness is equal to or less than 3. If it failed to scratch it, use a penny, the next hardest object. Continue with the procedure until the object is scratched and its hardness deduced.
3. Discover the characteristics of the minerals in the hardness scale. Fredrich Mohs chose the minerals for his scale because of their consistency: they always behave the same way. However, according to Tulane University, some minerals are unusual and exhibit inconsistent qualities, having a multitude of hardnesses along different lines of cleavage and crystal faces.
4. Create mnemonic memory verses to remember the minerals and their hardness order. Mnemonics are patterns of letters placed into verses to create memory devices. For example, in the following sentence,"The great Captain Fitch acted out quietly to capture dusk," the first letter of each word represents a mineral on the hardness scale, in the correct order. (Talc, gypsum, calcite, fluorite, apatite, orthoclase, quartz, topaz, corundum and diamond.) There are many well-known hardness mnemonics; unfortunately, most make use of inappropriate language. Feel free to create your own mnemonic verse.
Tags: hardness scale, relative hardness, apatite orthoclase, apatite orthoclase quartz, calcite fluorite, calcite fluorite apatite
