Alphabetical Index
Chemical Composition

Keyword Search
Named Inclusions
Steel Index

Exogenous Inclusions
Indigenous Inclusions

Macro Inclusions
Micro Inclusions
Nano Inclusions

Iron Oxide Inclusions
Nitride Inclusions
Oxide Inclusions
Phosphide Inclusions
Silicate Inclusions
Spinel Inclusions
Sulfide Inclusions

Refractory Inclusions
Slag Inclusions

Figure Browser

Help
Contact Us
Home

Quartz



Chemical formula: SiO2
Modifications: Several silica modifications are known. The following phases are stable at ordinary pressure: quartz - high quartz - tridymite - cristobalite - melt.
Melting point: 1710^oC
Stability range: <573 (low), 573-870^oC
Transformation temperature low-high: 573^oC
Density: 2.651 (low), 2.518 (high at 600^oC) g/cm3
Microhardnes: cca 1600 kp/mm2 (low)
Hardness (Moh's): 7
Luminescence: No data
Crystal system: Hexagonal
Cell dimensions: a=4.903, c=5.393 A
PDF number: 00-001-0649
ICSD number: 079634
Note: Low quartz in steel inclusions has been observed as dark grains which form more or less regular plates in polished sections.