A wooden box with nine minerals : talc, gypsum, calcite, fluor spar, apatite, orthoclase, rock crystal, topaz and corundum. Box includes a file with wooden handle and cloth.
Created by German mineralogist Fredrich Mohs in 1812, the Mohs Scale is ordered by hardness, determined by which mineral can scratch other minerals. It is based on the principle that a substance can scratch another substance that is softer, but not the other way around.
The Mohs Hardness Scale is used as a convenient way to help identify minerals.
Rocks are made up of one or more minerals. According to the scale, talc is the softest: it can be scratched by all other materials. Gypsum is harder: it can scratch talc but not calcite, which is even harder. The hardness of a mineral is mainly controlled by the strength of the bonding between the atoms and partly by the size of the atoms. It is a measure of the resistance of the mineral to scratching, the Mohs scale is for natural minerals. For manufactured products other measures of hardness are better.
In Mohs scale a pencil has the hardness of 1, a fingernail 2.5, window glass 5.5, a steel nail 6.5, a masonry drill bit 8.8, and diamond 10.
This kit was created by father and son Victorian natural history dealers.
date: 1866-1874
manufacturer: Bryce Wright
max dimension: 190mm
subject area: Social Science, Science
specific themes: Minerals, Technology, Geology
handling collection number: HC90