close box The applications which
can use this mineral are
highlighted. Please select
one to learn more.
Product Benefits
Technical Details

Quartz (silica, SiO2) is the core mineral within the Sibelco group and can be found in a broad number of applications, such as glass, ceramics and coatings. Quartz can be characterised by:


  • Relatively high Mohs hardness of 7
  • Low electrical conductivity
  • Easy to wet
  • High inertness in various media
  • Shape (depending on the source, quartz particles can have an angular or more rounded shape).


Note when using quartz:

depending on the particle size distribution of the product, it can be labelled (STOT RE 2 or STOT RE 1). For more detailed information, visit  www.safesilica.eu.


Basic properties

Property Value Unit
Moisture [%]
pH 7 [-]
Hardness (Mohs) 7 [-]
Refractive index 1.55 [-]
Colour (D65/ 10°) L* 93 – 96 [-]
L.O.I. < 0.3 [%]
Density 2.65 [kg/ dm3]


Product overview

product Grade D50 Grade D50 D90 OA
[µm] [µm] [µm] [g/ 100 g]
Silica sand M31 370 M6 30 95 16.5
M32 260 M10 23 60 17.5
M34 170 M300 17 40 19
M400 12 26 20
M500 4 10 23
M600 4 9 24
M800 1.8 4.1 32

Production locations Silica Sand



Silverbond is the brand name for Sibelco’s silica products.




  • Dirt pick-up resistance: the presence of quartz improves the coating’s resistance to dirt (from the atmosphere, for example).
  • Ease of tinting: due to the combination of refractive index, brightness and colour, paints containing fine quartz flour provide excellent reproducible colour results when working with tinting systems.
  • Texture effect: the use of coarse quartz grades provide texture to coating surface.
  • Tint retention: paints including fine quartz flour show improved tint retention over other minerals when subjected to natural weathering.
  • UV resistance and weatherability: due to its inertness, quartz supports good UV and weatherability performance to exterior architectural coatings.
  • Block resistance: with its non-stick properties, the use of quartz allows faster stacking of coated substrates without them sticking together.
  • Burnish resistance: due to its hardness of 7 on Mohs scale, quartz provides good burnish resistance (low tendency to become glossy when rubbed).
  • Gloss control: the gloss level of an interior coating can be regulated by selecting the appropriate grade of quartz.
  • Scrub resistance: due to its hardness of 7 on Mohs scale, quartz improves the wet-scrub resistance of interior decorative paints.
  • Stain resistance: quartz acts as a supporting mineral filler in stain resistant coatings.
  • Abrasion and scratch resistance: due to its fairly high hardness of 7 on Mohs scale, quartz provides abrasion and scratch resistance to the coating.
  • Chemical resistance: due to its inert nature, quartz provides good chemical resistance compared to conventional fillers.
  • Clarity: due to its fairly low refractive index, fine quartz grades become transparent when combined with certain binder systems.
  • UV-curing compatibility: being transparent for UV radiation, fine quartz grades do not block the curing mechanism.
  • Skid resistance: coarse quartz grades will give a roughness to the substrate, making it less slippery in general as well as under wet conditions, and provides better visibility in wet conditions.
  • IR reflection: quartz contributes to the IR reflection of roof coatings.
  • Pore and grain filling properties (sealer): with low impact on the viscosity, quartz can be used as a mineral filler in sealers to give them more body.


Sibelco © 2024