hardness scale

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Related to hardness scale: Vickers hardness scale

hard·ness scale

a qualitative scale in which minerals are classified in order of their increasing hardness, based on the fact that the harder of two materials will scratch the softer and will not be scratched by it. The scale lists 15 substances: talc (1); gypsum (2); calcite (3); fluorite (4); apatite (5); orthoclase, periclase (6); vitreous pure silica (7); quartz, stellite (8); topaz (9); garnet (10); tantalum carbide, fused zirconia (11); fused alumina (12); silicon carbide (13); boron carbide (14); diamond (15).
See also: Mohs scale.

Mohs scale

A system that qualifies minerals according to hardness, ranging from talc (1) to diamond (15).


Friedrich, German mineralogist, 1773-1839.
Mohs hardness number - a number on a mineralogic scale.
Mohs scale - a qualitative scale in which minerals are classified in order of their increasing hardness. Synonym(s): hardness scale
References in periodicals archive ?
The Russack hardness scale for bricks, as shown below, ranges from 0 to 10 on the scale; the higher the number, the more durable the brick.
Since 1997, NIST and other national metrology institutes have been working on the establishment of worldwide-unified Rockwell hardness scales (1).
0008" thick and has a hardness of 3200 to 3800 on the Vickers hardness scale.
With a refractive quality higher than a diamond and nearly identical on the hardness scale, moissanite will outshine and live alongside the most exceptional diamond.
Glass microspheres (Mohs hardness scale = 5-6) enable low oil absorption, reducing the amount of polymer required.
The new materials encompass the full SHORE A hardness scale (from 27 to 95) characterizing a wide range of rubber/elastomer based products.
The net effect is to extend the useful range of PUR elastomers downward on the hardness scale from currently attainable levels, BASF claims.
U-600 vulcanizates, for instance, are available in a relatively high hardness range, whereas all other grades give a vulcanizate hardness in the low to medium durometer A hardness scale.
MLB Prime bats are 9H rated - the highest rating possible on the ASTM's (American Society for Testing and Materials) 21-level universal hardness scale used to measure film hardness.
The CSUMX has the ability to cut through various ground formations ranging from 1 to 9 on the Mohs hardness scale.
Testing on the P&J hardness scale resulted in similar results, with the proprietary compound demonstrating superior thermal stability.