Durometer
it's hardness
The presence of buds at the nodes
gridlines
hammer
Most diamonds are used in industry and not in jewelry. Their hardness makes diamond useful as a cutting tool.
its low hardness score
Coating a tool with diamond renders the tool able to cut through its target, because of diamond's hardness, and to cut with precision.
it loses hardness at high temperatures.
The Janka Hardness Scale rates the hardness of hardwood flooring and bamboo as well. You can read more about the Janka Scale and see a list of the Janka Hardness Ratings from FindAnyFloor here http://www.findanyfloor.com/hardwood/JankaHardnessRatings.xhtml
S7 tool steel is produced and supplied to the machinist or tool maker in the annealed or soft condition. S-7 is typically heat treated and used in the Rockwell C hardness range of RC 54-59. Form more specific information about S-7 tool steel and heat treating, see the related links below.
required red hardness n wear resitence at elevated temprature
The hardness of minerals can be determined using the Mohs scale, which ranks minerals from 1 (softest) to 10 (hardest). To test hardness, one can scratch a mineral with a known hardness or use a tool like a fingernail, copper penny, or steel file to compare the resistance to scratching.